Alloy-Effect of Alloying Elements in Iron and Steel.pdf

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By JGC Annamalai
(IN IRON AND STEEL)
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Effects of Alloying Elements in Iron and Steel Page
A0 Alloys of Iron and Steel-Cover Page 1
A1 Alloys of Iron and Steel - Content / Chapters List 2
A2 Alloys of Iron and Steel, General 3
A3 Effect of Alloying Element-General 4
A4 Effect of Alloying Element-Carbon, on Steel and on Welds 6
A5 Effect of Alloying Element-Manganese, on Steel and on Welds 11
A6 Effect of Alloying Element-Silicon, on Steel and on Welds 13
A7 Effect of Alloying Elements, other than C, Mn, Si 15
A8 Effect of Impurities, like Sulfur, Phosphorus, Boron etc. 19
A9 Effect of Alloying Elements, on Iron-Carbon Diagram 22
Annextures :
B1 Spectrometers 24
B2 Alloy Element, Detection and Analysis (Chemical, XRF, OES, LIBS) 25
B3 Detection Methods, Compare 29
B4 Checklist of Features 31
B5 Elements and Atoms 32
B6 Top Ten Strongest Alloys 35
B7 Superalloys and High Alloys 39
B8 Glossary for XRF, OES, LIBS . . . . Methods 48
Total Pages 54
Chapter-A1 (Topics) Chapter List
Authored by R.Annamalai, (former Chief Equipment Engineer, JGC Corporation), rannamalai.jgc@gmail.com
Effects of Alloying Elements, In Iron & Steel By JGC Annamalai
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Chapter-A2
(1). Alloys are usually harder and stronger than their components but very often less ductile and less malleable. (Hardness
of gold is increased by addition of copper to it).
(2). The melting point of an alloy is always lower than the melting points of the constituent metals.
(3). Other properties such as reaction(corrosion) towards atmospheric oxygen and moisture, mechanical strength, ductility,
color etc, also undergoes a change when alloy is made from its constituents metals.
This change of properties are very useful and makes an alloy beneficial.
Plain Carbon Steels : Steel is theoretically an alloy of iron and carbon. When produced commercially however,
certain other elements such as manganese, silicon, sulphur and phosphorus are inevitably present in small quantities.
These elements are not intentionally added. They are present from the ores or due to processing. When these four
elements are present in their normal amounts, the product is referred to as Plain Carbon Steel.
Alloy is one which contain two or more elements (like Fe, Cr, Ni, Mo, V, Ti, etc) other than carbon, manganese and
deoxidation elements(Si, Mn, Al) and impurities. Most of the cases the chemical elements are in solid solution
Effects of Alloying Elements, in Iron & Steel,
Alloys of Iron and Steel
An alloy is a homogenous mixture of metals, or a metal combined with one or more other elements. Elements in alloy are
in solid solution of the elements and normally have different melting, corrosion resistance, electrical properties.
AISI specifies, Carbon steel is an iron-carbon alloy, which contains up to 2.1 wt.% carbon. For carbon steels, there is no
minimum specified content of other alloying elements.
The maximum allowed: manganese is 1.65%, max. silicon is 0.6% and max. copper should be less than 0.6%.
Popular alloys : (1). Brass, (Cu >50%, remaining Zinc); (2). Bronze, (Cu>60%, remaining Tin); (lead, tin, iron, aluminum,
silicon, and manganese are also found in Brass and Bronze); (3). Gun Metal, (Cu>65, remining, zinc and tin), (4).
Commercial Gold (Gold and silver or copper), (5). steel (iron+carbon), (6). stainless steels (Iron, chromium, nickel,
molybdenum etc), (7). solders (lead+tin), (8). Electrical Element (Nickel+chrome), (9). stellite (cobalt+chromium)
By JGC Annamalai
3

Effects of Alloy
Element in Steel
(%)
Percentage
Positive Effects Negative Effects
Carbon increasing C% Strength Ductility
Hardness Weldability
max. 2.0% Hardenability
Manganese 0.30/1.15 Surface Quality Machinability
(Favoring MnS to FeS inclusions) Weldability
Strength Machinability
1.20/1.65 Surface Quality Weldability
Over 1.65 Hardenability Machinability
Weldability
Phosphorus 0.040 Max (No special benefits) Ductility, Toughness
0.04/0.12 Machinability Ductility, Toughness
(Desirable chip formation) Impact Resistance
Sulfur Under ~ 0.006 Surface Quality Machinability
(Due to absence of sulfur) (Poor chip formation)
0.01/0.05 (No special benefits) Chemical Impurity
0.06/0.40 Machinability Traverse Properties
Additive Impact Resistance
Weldability
Cold Formability
Silicon 0.10/0.40 Deoxidizer Machinability
Over 1.00 Strength of Ferrite Machinability
Sag Resistance Decarburization
(Spring Steel)
Nickel 0.01/0.25 Strength (Microalloy) Machinability
0.30/0.80 Hardenability Machinability
~1.00/4.00 Low-Temperature Machinability
Toughness
Chromium 0.01/0.25 Strength (Microalloy) Machinability
0.30/0.80 Hardenability Machinability
~1.00/2.00 Abrasion Resistance (Carbide Formation) Machinability
High Temperature Strength
Hardenability
Molybdenum 0.08/.060 Hardenability Machinability
Creep Strength Weldability
High Temperature
Strength
Copper 0.20 Max. Strength (Microalloy) Surface Quality
0.20/0.50 Corrosion Resistance Surface Quality
Forgeability
Over 1.00 Yield Strength (Alloy) Ductility
Impact Resistance
Forgeability
Nitrogen 0.020 Max. Strength (Microalloy) Cold Formability
Yield Strength (Microalloy) Ductility
Aluminum 0.95/1.30 Deoxidizer Machinability
Grain Refiner
Ability to Nitride
Columbium Deoxidizer Machinability
Grain Refiner Weldability
Strength (Microalloy) Toughness
Carbide Formation Hardenability (via Carbon Impoverishment)
4

Effects of Alloy
Element in Steel
(%)
Percentage
Positive Effects Negative Effects
Vanadium 0.05/0.20 Deoxidizer Machinability
Grain Refiner Ductility
Strength (Microalloy)
Wear Resistance
Titanium Deoxidizer Machinability
Grain Refiner
Nitrogen Scavenger
Boron 0.0005 Min. Hardenability Weldability
Nitrogen Scavenger Low-Temperature
Toughness
Lead/Bismuth 0.10/0.40 Machinability Embrittlement @ 600+ Degree F
Tellurium Machinability Surface Quality (Member of Sulfur Family)
(Sulfide Inclusion Modifier)
Calcium Machinability Susceptibility to Rolling Contact Fatigue
Inclusion Modifier
Desulfurization
Castability
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Chapter-A4 Effect of Carbon on Steel Castings and on Welds
(1)
(2)
(3)
Applications:
Carbon Equivalents :
Mild Steel: (Carbon <0.3%)
i) Dead mild steel is used for making steel wire, sheet, rivets, screws, presssure vessel, pipe, nail, chain, etc.
ii)
iii)
Medium Carbon Steel: (Carbon 0.3 to 0.7%)
i)
ii)
iii)
High Carbon Steel: (Carbon 0.7 to 1.5%)
i)
Welding: Increasing the
carbon content over 0.3% or
carbon equivalent over 0.4%
reduces the weldability. Extra
care like Cleaning, low residual
stress, Preheat, Electrode
selection (low hydrogen
electrodes) etc, should be
taken to prevent Cracks.
Steel containing 0.6 to 0.7% carbon is used for drop forging die & die
blocks, clutch, discs, plate punches, set screws, valve springs, cushion ring, thrust washers, etc.
Mild steel containing 0.2 to 0.3% carbon is used for making valves,
presssure vessel, pipe, gears, crank shafts, connecting rods, railways
axles, fish plates and small forgings, etc.
Steel containing 0.35 to 0.45% carbon is used for connecting rod, wires
& rod, spring, clips, gear shaft, key stock, shafts & brakes lever, axle,
small & medium forgings, etc.
Steel containing 0.45 to 0.55% carbon is used for railways coach axles,
axles & crank, pins on heavy machines, spline shafts, crank shafts, etc.
High Carbon Steel: High %C content provides high hardness and strength. Hardest and least ductile. Used in hardened
and tempered condition. Strong carbide formers like Cr, V, W are added as alloying elements to from carbides metals.
Used as tool and die steels owing to the high hardness and wear resistance property.
Medium Carbon
Steel
0.5 to 2.0%
0.3 to 0.5 Used where no welding is used and strength is required
; certain amount of ductility is desired
Low Carbon Steel: Most abundant grade of steel is low carbon steel ( greatest quantity produced; and least expensive).
Not responsive to heat treatment; sometime, cold working needed to improve the strength.
It has good machinability, formability, weldability . Use: Pressure vessels, pipes, structures etc.
Medium Carbon Steel: It can be heat treated - austenitizing, quenching and then tempering. Most often used in
tempered condition – tempered martensite. Medium carbon steels have low hardenability. Addition of Cr, Ni, Mo
improves the heat treating capacity. Heat treated alloys are stronger but have lower ductility. Use: Railway wheels and
tracks, gears, crankshafts.
Effects of Alloying Elements, In Iron & Steel
Components, having no
bending, no welding,
0.02 to 0.3
Steel or Iron Group
% carbon
Low Carbon Steel Used to make pressure vessel components for its
good weldability and impact strength. Mild Steel (MS).
Steel Character Applications
Components, having,
bending, welding
High Carbon Steel
Metals can be classified as Ferrous metals and non-ferrous metals. More than 60% of metals used, are ferrous metals.
Pure iron(100% Fe) is very soft and not used as engineering materials. So, iron is alloyed(steel and cast iron) to get the
most desirous properties. There are many elements alloyed with iron, to get various properties. Carbon is the first alloying
element in iron and steel group. Carbon is already present in iron from Blast Furnace and carbon is reduced to get various
iron and steel grades.
First group of alloying element is Carbon. Carbon is the major element, alloyed with iron. Iron and Carbon makes steel
and cast iron. More than 70% ferrous metals are steel. As carbon increases, strength increases and hardness increases
and ductility is reduced.
Used in tools where strength is important and ductility is
not much required and no welding. Springs
AWS says, steel CE over 0.4%,
produces, Cracks on welds and
HAZ
Mild steel containing 0.15 to 0.2% carbon is used for making camshafts, sheets, strips, for blades, presssure
vessel, pipe,welded tubing, forgings, drag lines, etc.
Steel containing 0.7 to 0.8% carbon is used for making cold chisels, wrenches, jaws for vice, pneumatic drill bits,
wheels for railway service, wire for structural work, shear, blades, automatic clutch disc, hacksaws, etc.
Cold working on steel with CE>0.4
is difficult and may lead to crack.
By JGC Annamalai
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By JGC Annamalai
ii)
iii)
iv)
v)
vi)
vii)
Iron & Steel Manufacture :
Blast Furnace: Coke (C) burns with air(O2) and gives out intense heat. In the high temperature, iron ore mixes with O2 and
forms iron, per above reactions. This is the pig iron or cast iron. Later in Bessemer or Electric Arc Furnace: liquid cast iron is
poured and blown with oxygen, to reduce the carbon level below 2%. AOD Furnace: Carbon level below 0.1% is reduced.
Steel containing 1.3 to 1.5% carbon is used for making wire drawing dies, metal cutting saws, paper knives, tools for
turning chilled iron, etc.
Steel containing 1.1 to 1.2% carbon is used for making taps, thread metal dies, twist, drills, knives, etc.
Steel containing 1.2 to 1.3% carbon is used for making files, metal cutting tools, reamers, etc.
Steel containing 0.8 to 0.9% carbon is used for making rock drills, railway rail, circular saws, machine chisels,
punches & dies, clutch discs, leaf springs, music wires, etc.
Steel containing 0.9 to 1.0% carbon is used for making punches & dies, leaf & coil, springs, keys, speed discs,
pins, shear blades, pre-stressed load bearing cables , etc.
Steel containing 1.0 to 1.1% carbon is used for making railway springs, machine tools,mandrels, taps, etc.
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By JGC Annamalai
As we add carbon to steel, the following properties are changed:
Advantages: (1). Tensile , Yield Strength are increased, (2). Hardness is increased
Dis-advantages: (1). Ductility(%-Elongation& Area Reduction) is reduced, (2). Impact value reduced, (3). Difficult Welding.
Methods of Strengthening Steel:
1) Alloying (the main line for high strength steel).
2) Heat-treatment
3) Cold work / rolling, Grain refinement.
4) Martensitic transformation / heat treatment, ageing
1)
Alloying is the mixture of elements in solid solution.
2) Heat Treatment (Quenching & Tempering) :
3)
Grain Size : Ductility, Formability- Fine Grained (number of grains are more,
grain size is smaller), Compared with course grained material :
ASTM A656, A572, -Microalloyed steels, HSLA (High Strength Low-Alloy), MS
steels, are strengthened by adding “micro” alloy (niobium, vanadium, titanium,
molybdenum or boron, Thermomechanical processing) concentrations to low-
Pure iron (100%Fe) is highly soft and useless as Engineering or
construction material. Carbon is already present in steel. To add
further strength, Fe is alloyed in liquid state, by addition of silicon,
manganese, chromium, molybdenum, nickel, vanadium etc.
Alloys may take up position either in interstitial alloys or in
substitutional alloy positions. The larger atomic mass of solute in
the atomic lattice structure of iron, will distorts the iron slip planes
thus causing the strength to increase. Other than carbon, elements
like chromium, nickel, vanadium, molybdenum, tungston, cobalt
etc. have atomic sizes larger in size and added as solute in liquid
state of steel to increase the steel strength.
Alloying:
TMT Bars are Thermo-Mechanically-Treated through leading world tempcore
based technology for high yield strength. The process involves rapid quenching of
the hot bars through a series of water jets after they roll out of the last mill stand.
(1). They are hard, have a higher yield strength, and are not ductile. Ductile material forms
better with less cracking, tearing, or orange-peeling.
Heat Treatment is the major method of strengthening steel. Steels
having < 0.3%C are difficult to heat treat and increase the steel
strength. Often Steels >0.35%C are strengthened by heat treatment
(heating above A3 line in Austenitic state and water or oil quenched
and later tempered).
IS-1786, The process involves rapid quenching of the hot bars through a series of
water jets after they roll out of the last mill stand. The bars are cooled, allowing the
core and surface temperatures to equalize.
Maraging Steels, having 18%Ni, 9%Co, 5%Mo, 0.6%Ti, 0.1%Al, TS=2000 MPa
(290ksi), with 95%cold work and aging are used in Space Craft and where high
strength material is necessary.
There are materials(like austenitic SS) which do not change their
strength due to heat treatment. Carbon content cannot be easily
increased. Some cases, increasing carbon, may have negative
impact. So, other methods of strength improvement like cold work or
strain hardening is followed.
of dislocations can impede dislocation motion by repulsive or attractive interactions.
Output of Blast Furnace is Cast Iron, Fe with 3 to 4%C. As the
output is poured in forms of pig shape, it is called pig iron.
Reduction of carbon with air or oxygen, in the Besser Furnace,
Arc Furnace etc. changes the cast iron to steel.
The primary species responsible for work hardening are dislocations.
Dislocations interact with each other by generating stress fields
Dislocations interact with each other by generating stress fields in the material. The interaction between the stress fields
Low carbon steel materials are normalized or annealed. Medium and
high carbon steels are heated and tempered to get soft steel (tensile
and yield strengths are reduced, hardness is reduced, ductility
increased, impact value increased).
Cold work(also called work hardening, strain hardening) / rolling,
Grain refinement, Annealing or Normalizing.
Interstitial
Alloy
Substitutional
Alloy
8

By JGC Annamalai
4) Grain Boundry Strengthening :
5) Martensitic transformation, heat treatment, ageing
Grain-boundary strengthening (or Hall–Petch
strengthening) is a method of strengthening
materials by changing their average crystallite (grain)
The reasons for Martensite, stronger and harder:
This phenomenon has been termed as the reverse or inverse Hall–Petch
relation.
When martensite forms, there is no time for the formation of
cementite and the austenite transforms to a highly distorted
form of ferrite which is super saturated with dissolved
carbon. The combination of the lattice distortion and the
severe work hardening resulting from the shear deformation
processes, cause martensite to be extremely strong but
very brittle
or decrease with decreasing grains size.
When heated ferrous alloys (Fe-C or Fe-Ni-C or Fe-Cr-C or Fe-Mn-C) in the Austenitic state (but below 60% Melting
Point), (a). rapidly cooled , Austenite (FCC) changes to Martensite (BCT, Body Centered Tetragonal), (b). Slow cooled
Austenite canges to Bainite or Ferrite or Cementite(BCC).
Theoretically, a material could be made
infinitely strong if the grains are made
infinitely small. This is impossible though,
because the lower limit of grain size is a
single unit cell of the material.
However, experiments on many
nanocrystalline materials demonstrated
that if the grains reached a small enough
size, the critical grain size which is typically
around 10 nm (3.9×10
−7
in), the yield
strength would either remain constant.
Relatively low cost, low carbon martensitic steels, having
high strength to weight ratio, is substitutes for plastics and
fiber glass, can compete with high carbon quenched and
tempered or austempered steels as well as such high priced
materials as aluminum, titanium, and stainless steel.
Strength and Hardness of Martensite > Bainite > Fine
Pearlite > Course Pearlite
Martensitic has a BCC-tetragonal crystal structure. It is an
intermediate structure between the normal phases of iron-
FCC and BCC.Lattice shear and surface distortion results in
the formation of a typical needle like martensitic structure.
Martensitic transformation is a diffusionless transformation.
Martensite has super saturated carbon atoms in the BCT
crystal.
By changing grain size one can influence the number of dislocations piled up at the grain boundary and yield strength.
For example, (a). heat treatment after plastic deformation and (b). changing the rate of solidification are ways to alter
grain size.
When the grain size is increased, the strength and hardness are decreased and the material is softened. Increasing
grain size, decreases the amount of possible pile up at the boundary, decreasing the amount of applied stress necessary
to move a dislocation across a grain boundary. The higher the applied stress needed to move the dislocation, the higher
the yield strength.
The Hall–Petch Relation : As the grain size decreases, the yield strength increases.
(2). A finer grain size means more grain boundaries,
and more grain boundaries means a greater
resistance to dislocation. It is the measured ability of
a material to withstand serious plastic deformation,
making the material less ductile.
The more grains we have, the more slip planes are
oriented in a similar direction and therefore, there will
be a greater amount of deformation without failure,
like cracking, splitting, or orange-peeling therefore,
there will be a greater amount of deformation without
failure, like cracking, splitting, or orange-peeling
9

By JGC Annamalai
0.05 Dead mild Steel
0.084-0.15 Mild Steel
0.15 Mild Steel
0.10-0.30 Mild Steel
0.254-0.40 Medium carbon Steel
0.30-0.45 Medium carbon
0.40-0.50 Medium carbon
0.554-0.65 High carbon Steel
0.95-1.10 High carbon Steel Knives, axes, screwing taps and dies, milling cutters
Punches, shear blades, high tensile wire
Chisels, die blocks for forging
Hammers, saws, cylinder liners
Forging dies, springs, railway rails
%Carbon Name
Sheet, strip, wire, rod, nails, screws, reinforcing bars
Sheet, strip, car bodies, tinplate, wire, rod, tubes
Shafts, gears, forgings, castings, springs
High tensile tube, shafts
Bright drawn bar
Steel plate, tube, pipe, structural steel sections for welding
Case carburizing type
Applications
ASTM grain size number(n) is
related with, the number of
grains(N) that we can count, in
one sq.inch, in 100X
magnification by the relation,
N=2
(n-1)
. So ASTM grain size
number increases with
decreasing grain size.
Plain carbon steels are broadly classified as:
Low carbon or mild steel (0.05-0.3%C), with high ductility and ease of forming;
Medium carbon steel (0.3-0.6%C), in which heat treatment can double the strength and hardness but retain good ductility;
High carbon steel (> 0.6%C), which has great hardness and high strength and is used for tools, dies, springs, etc.
10

Chapter-A5
1)
2)
3)
4)
Effect of Manganese, as an Alloying
Element :
Manganese is a hard, brittle, silvery white metal derived from the Latin word 'magnes', meaning magnet. Originally
discovered in 1774, manganese is the fifth most abundant metal present on the Earth’s crust. Pre-historic cave painters of
the French’s Lascaux region used this metal in the form of manganese dioxide or black ore pyrolusite, 30,000 years ago.
Effects of Alloying Elements, in Iron & Steel
Manganese in the form of Fe-Mn or Si-Mn is consumed in bulk form primarily in the production of steel, which is intentionally
present in nearly all steels, is used as a steel desulphurizer(Mn has more affinity with S and forms MnS, a low melting point-
low density slag) and as deoxidizer(Mn has more affinity to oxygen and forms MnO, a low melting point, low density slag).
Mn improves the tensile strength, workability, toughness, hardness and resistance to abrasion. By removing S from steel,
Mn prevents the steel from becoming brittle during the hot rolling process.
Manganese is used in Iron & Steel Industry as (1). Deoxidizer(oxygen killer), as (2). Desulphurizer, and as (3). Hardening
(Strengthening) element. Manganese is used also as an alloy with metals such as aluminum and copper.
In Steel, as we increase Manganese
addition, the γ loop increases at the
bottom. A1,A2,A3 lines are moving
down, A4 line is moving up.
Steel containing 8-15% manganese can have a high tensile strength of up to 863 MPa, and steel with 12% or more
manganese is used in applications in which great toughness and wear resistance is required, such as gyratory crushers, jaw-
crusher plates, railway points and crossover components.
Manganese up to 3% is used to make alloys of Aluminum, copper etc for deoxidization, higher strength, better castability,
better workability, resistance to corrosion etc. Also used, in battery, lubrication additive, as pigment in paint, glass, ink, used
in printed circuit board manufacture, etc.
Manganese : Manganese is the second common alloy element in iron and steel. Manganese is very essential element, to
make steel. In the iron & steel Industry alone, 85 to 90% produced Manganese is consumed. 30% Manganese or ferro-
manganese is used in Blast Furnace to purify the iron melt, and 70% Manganese is used in Bessemer Furnace or Electric
Arc Furnace and in ladle, to remove unwanted Sulfur, Phosphorus, oxygen as slag and for alloying. Manganese also helps
to dissolve more nitrogen, in to the liquid steel. AISI allows, manganes up to 1.65% in steel .
Austenite SS, uses Manganese as a replacement for costly Nickel as Austenite former. Now, nitrogen and mangenese are
partially replacing Nickel as Austenite former(SS200 series). For various special purpose (like cryogenic applications and
for low temperature applicaitons), additional Manganese is added to steel, as it improves impact properties at low
On normal case of CS, AISI, allows, max: manganese,1.65%, max. silicon, 0.6% and max. copper, 0.6%.
Effect of Manganese on Steel and on Welds
In the annealed alloys of high manganese or
low mangenese content, appears to have no
influence on grain size(when we cool
rapidly(normalized) or slowly (annealed) ;
In specimens which were cooled more
rapidly—that is, normalized—the grains of the
alloys of high manganese content were very
much smaller than in similar alloys of lower
manganese. This structural feature also has
its effect upon the mechanical properties.
Manganese is used in carbon steel as
deoxidizer, "desulphurizer," and as a
hardening element.
The effect of manganese may be
described as a "restraining" influence, so
that pearlite in carbon steels even after
annealing has a fine-grained sorbitic
structure similar to rapid cooling. The
mechanical properties are correspondingly
raised.
The eutectoid ratio of carbon steels is reduced
by 0.1% of carbon for every 1 %
manganese(or for every 1% Manganese to
steel, Eutectoid point, moves to the left, by
0.1% in Carbon. For 9% Mn, the A1 line is
lowered to 650°C from 726°C, A3 line is
lowered from 912°C to 750°C
By JGC Annamalai
11

Chapter-A5 Effect of Manganese on Steel and on Welds
By JGC Annamalai
Effect of Manganese, as an Alloying Element :
1)
2)
3)
4)
5)
6)
7)
8)
9).
10)
<0.4% Mn in steel, is used to de-sulfurize the steel and reduce hot-shortness.
Manganese is one of the least expensive of alloying elements and is always present as a deoxidizer and to reduce hot
shortness.
>0.8% Mn, in steel, when the manganese content exceeds 0.80%, it acts as an alloying element to increase the strength
and hardness in high carbon steels. Fine-grained manganese steels have excellent toughness and strength.
>10% Mn in steel, remain austenitic after cooling and are known as Hadfield manganese steel. After heat treatment, this
steel has excellent toughness and wear resistance as well as high strength and ductility. Work hardening occurs as the
austenite is strain hardened to martensite
(a). For welding purposes, the ratio of manganese to sulphur should be at least 10 to 1. Manganese content of less than
0.30% may promote internal porosity and cracking in the weld bead. Cracking can also result if the content is over 0.80%.
Steel with low Manganese Sulphide ratio may contain sulphur in the form of iron Sulphide (FeS), which can cause cracking
(a “hot-short” condition) in the weld.
(b). As a sulphide former, Manganese prefers to combine with S and forms manganese sulfide, avoiding the formation of
iron sulphides and starts floating at liquid state. Iron sulphides are the low melting point phases that become liquid at hot
rolling temperatures and which, consequently, generate surface cracking.
(c). Manganese can form manganese sulfide (MnS) with sulfur and helps the machining, and simultaneously prevents the
brittleness from sulfur, making it useful for the surface finish of carbon steel.
(d). Addition of Manganese to steel, will move the Eutectic point close to the Y-axis(0% Carbon) and lower the Eutectic
Temperature , say, average, carbon- 0.12%C and Eutectic temperature 9°C is reduced for every 1% manganese addition.
This will help Forging Vendors and Heat Treaters, to reach the Austenitising temperature for forging, heat treatment etc.
faster and at more economical way. 9% manganese addition, lowers the Eutectic point to Carbon=0.4% and
temperature=650°C, from normal 0.8%C and 726°C. A3 point is moved to 740°C from 912°C.
For Better Welding: a). Mn:S ratio 10:1, b). max.0.3%Mn to reduce porosity, c). Max.0.8%Mn to reduce welding cracks.
Used as an active deoxidizer
Less likely to separate than other alloying elements
Enhances machinability by integrating with sulfur to form a soft inclusion in the steel, enabling a consistent built up edge
along with a place for the chip to break
Enhances yield at the steel mill by integrating with the sulfur in the steel and reducing the formation of iron pyrite, which
can make the steel susceptible to crack and tear during high temperature rolling processes
It boosts the tensile strengh and hardenability, but reduces ductility. Even annealed steel, has fine grained structure.
It integrates with sulfur to form globular manganese sulfides, which are required in free cutting steels to ensure good
machinability
The manganese has restraining influence that in carbon steel, pearlite even after annealing has a fine-grained sorbitic
structure such as results ordinarily found upon more rapid cooling. The mechanical properties are correspondingly
raised.
Higher Manganese, supports the carbon penetration during Carburizing.
Addition of Manganese lowers A3 line down and moves the steel Eutectoid point to left (or lowers the % of carbon),
resulting in lower forging temperature and cooling rate.
12

Chapter-A6
Galvanizing : Elements like, carbon in excess of about 0.25 %, phosphorus in excess of 0.04 %, or manganese in excess
of about 1.3 % in steel will cause unacceptable coatings with a mottled or dull gray appearance. Steels with silicon in the
range 0.04 % to 0.15 % or above 0.22 % is said to have excess galvanizing growth effect. Highly cold worked objects are
said to have high residual stresses and aging. These steels will have embrittlement on galvanizing.
Though Silicon is abundant on the Earth Crest(about 90% is silicon salts), it is seldom found as elemental Silicon. Silicon
has high offinity to oxygen and forms SiO2 immediately (normal sand). Among the common deoxidizers, like carbon,
manganese, aluminum, silicon find first place. Silicon in the form of Ferro-silicon, Silico-Manganese are used as
deoxidizer(also called oxygen killer, oxidizer) in the steel industry and as easy-flow aiding agent in liquid metals in
Foundries. Silicon, along with Manganese is used in Steel Industry as (1). Deoxidizer(oxygen killer), as (2). Desulphurizer,
and as (3). Hardening (alloying) element. Large number of silicates are found in the Cement and in refractories. On plain-
carbon steels, max.0.6% silicon is allowed. Foundries, may use up to 1.5%Si. Solidum silicate or Silicate oil is used as
binder in sand molds in the foundries and in electrode flux coating.
Silicon is not welcome in iron and steel in some grades, like steel used for galvanizing purpose. Silicon and zinc forms Fe-Si
alloy compound and often silicon over 0.4% in galvanized iron and steel, causes the surface darker and may need
additional zinc deposit to zinc to compensate silicon and to shine white.
After the invention of semi-conductors and use of Silicon in semi-conductors, chips, solar panels, electronic and
instrumentation and in computers etc from 1960, the use of pure silicon has incresed, many folds.
Silicon steel or electrical steel (Si up to 6%) is used in electrical motor and transformer coil laminations. They have lower
hysterisis and eddy current losses.
Hot Work : Similar to Mn, silicon also gives higher strength and hardness. However, larger percentage of Silicon, leads to
cracking during rolling and other hot works and Silicon over 0.04% should be avoided. Foundries(where Hot Forming work
is not involved, like, valves, pumps etc castings), may use up to 1.5% Si, to have better liquid metal flow inside mold voids.
Effect of Silicon on Steel and on Welds
Castings (Foundries) : Silicon is
added to cast stainless steel
grades to increase casting fluidity
and improve castability. As
carbon plus silicon content is
increased, partial eutectic
solidification improves castability
and casting soundness. Silicon is
generally limited to 1.5% in
castings intended for service
above 1500°F (815°C) because it
lowers the high temperature
creep and rupture properties.
Castings intended for service
above 1500°F (815°C), silicon is
generally limited to 1.5%
because it lowers the high
temperature creep and rupture
properties.
In carburizing atmospheres such as ethylene furnaces, silicon levels as high as 2% have been found to be beneficial. .
Silicon also improves oxidation resistance, particularly where elements with a volatile oxide such as tungsten or niobium
(columbium) are used to improve high temperature strength.
For galvanizing purposes, steels containing more than 0.04% silicon can greatly affect the thickness and appearance of the
galvanized coating. This will result in thick coatings consisting mainly zinc-iron alloys and the surface has a dark and dull
finish. But it provides as much corrosion protection as a shiny galvanized coating where the outer layer is pure zinc.
By JGC Annamalai
13

Chapter-A6 Effect of Silicon on Steel and on Welds
By JGC Annamalai
Lamination sheets for Transformers, motors etc : Electrical Steel :
Ill Effects of Silicon :
For galvanizing purposes, steels containing more than 0.04% silicon can greatly affect the thickness and appearance of
the galvanized coating. This will result in thick coatings consisting mainly zinc-iron alloys and the surface has a dark and dull
finish. But it provides as much corrosion protection as a shiny galvanized coating where the outer layer is pure zinc.
Silicon increases the electrical resistivity of iron by a factor of about 5; this change decreases the induced eddy currents and
narrows the hysteresis loop of the material, thus lowering the core loss by about three times compared to conventional
steel.Electrical steel is an iron alloy which may have from zero to 6.5% silicon (Si:5Fe). Commercial alloys usually have
silicon content up to 3.2% (higher concentrations result in brittleness during cold rolling). Manganese and aluminum can be
added up to 0.5%.
Electrical steel (lamination steel, silicon electrical steel, silicon steel, relay steel, transformer steel) is an iron alloy tailored to
produce specific magnetic properties: small hysteresis area resulting in low power loss per cycle, low core loss, and high
permeability.
Electrical steel is usually manufactured in cold-rolled strips less than 2 mm thick. These strips are cut to shape to make
laminations which are stacked together to form the laminated cores of transformers, and the stator and rotor of electric
motors. Laminations may be cut to their finished shape by a punch and die or, in smaller quantities, may be cut by a laser,
or by wire
In welding, silicon is detrimental to surface quality, especially in the low carbon, resulphurized grades. It aggravates
cracking tendencies when the carbon content is fairly high. For best welding condition, silicon content should not exceed
0.10%. However, amounts up to 0.30% are not as serious as high sulphur or phosphorus content
14

Chapter-A7
Impurities, Phosphorus :
Alloying Element : Chromium :
Alloying Element : Nickel :
When chromium in steel exceeds 1.1%, a
surface layer is formed and protect the steel
against oxidation at elevated temperatures,
scaling and sulfer corrosion. It contributes to
high temperature creep and rupture strength;
and, it helps to increase resistance to
carburization.
Nickel increases resistance to oxidation, carburization, nitriding, thermal fatigue, and strong acids, particularly reducing
acids. It is an important alloying element in stainless steel and nickel-base alloys used for corrosive and high temperature
applications. Adding nickel improves toughness, ductility, and weldability.
Effect of phosphorus element will have various effects on steel depending on concentration. The maximum amount of
phosphorus in higher grade steel is between 0.03 to 0.05% due to the fact that is detrimental. Up to 0.10% of phosphorus in
low-alloy high-strength steels will increase the strength as well as improve the steel's resistance against corrosion. The
possibility of brittlement increases when the content in hardened steel is too high. Even though the strength and hardness is
improved, the ductility and toughness decreases.
Machinability is improved in free-cutting steel, Phosphorus also affects the thickness of the zinc layer when galvanising
steel.
Welding : Weld is brittle and/or weld will crack if the phosphorus content is more than 0.04%. The surface tension of the
molten weld metal is lowered, making it difficult to control and to work in overhead(4F/4G) position.
Impurities, Sulfur : (also discussed in Chapter-A8. Chapter-8 is specifically for
Stainless Steel)
Chromium is a powerful alloying element in
steel. Min of 10.5% of Chromium provides,
shining passive layerof chromium oxide on
the surface.
Sulfur is normally regarded as an impurity and has an adverse effect on impact properties
when a steel is high in sulphur and low in manganese. Combining with Manganese, Silicon,
Iron, the sulfur forms alloys of low melting points. When liquid metal solidifies, they stay as
liquids till all iron has solidified and liquid sulfur alloys fills the last phases of the solidification
front. These alloys have very low strength and often causes hot shortness and considered
main reason for hot cracking during welding and during casting solidify
Sulphur improves machinability but lowers transverse ductility and notched impact toughness
and has little effects on the longitudinal mechanical properties. Its content is limited to 0.05%
in steels but is added to free cutting steels in amount up to 0.35% with the manganese
content increased to counter any detrimental effects since alloying additions of sulfur in
amounts from 0.10% to 0.30% will tend to improve the machinability of a steel. Such types
may be referred to as "resulfurized" or "freemachining". Free cutting steels have sulphur
added to improve machinability, usually up to a maximum of 0.35%.
Even though the effect of sulphur on steel is negative at certain stages, any sulphur content
less than 0.05% has a positive effect on steel grades.
Major causes of hot cracking are : Segregation of impurity and minor elements such as
sulphur, phosphourous, silicon, niobium, boron etc to form low melting eutectic phases.
Fully Aus.SS can have improved hot-crack resistance, comparable to SS304, if the
segregation of phosphorus and sulfur at grain boundries are restricted to 0.002%
Although it increases the tensile strength of steel and improves machinability it is generally regarded as an undesirable
impurity because of its embrittling effect during hot rolling and other hot forming operations.
It is primarily used with nickel and copper to
increase hardenability, to increase the
corrosion resistance, yield strength of the
steel. Stainless steels may contain in excess
of 12% chromium. The well-known “18-8”
stainless steel contains 8 % nickel and 18 %
chromium.
Effect of Elements, (other than C,Mn, Si) in Steel and in Welds
By JGC Annamalai
14
By JGC Annamalai
15

Chapter-A7 Effect of Elements, (other than C,Mn, Si) in Steel and in Welds
By JGC Annamalai
By JGC Annamalai
Alloying Element : Molybdenum :
Alloying Element : Vanadium :
Alloying Element : Tungsten :
Alloying Element : Cobolt :
Cobalt improves strength at high temperatures and magnetic permeability
Alloying Element : Nitrogen :
Alloying Element : Boron :
Alloying Element : Titanium :
Alloying Element : Niobium (Earlier name was Columbium)
Nickel is austenite former. Min.7% Chromium, makes the stainless steel as Austenitic Stainless Steel.
Nitrogen acts very similar to Carbon in the alloy. N substitutes C in small amounts (or even large, with modern technologies)
to increase hardness. Obviously, Nitrogen forms Nitrides, not Carbides. INFI has N, and there's few more, with Sandvik
being the champion, having 3% N in the alloy, completely substituting C. Sadly, not available for knife makers. Because
Nitrogen is less prone to form Chromium nitrides than Carbon is to form Chromium carbides, its presence improves
corrosion resistance, leaving more free Chromium in the alloy. Since Nitrogen is less reactive in forming Nitrides, it can be
used for added hardness without increasing carbide size and volume, e.g. Sandvik 14C28N steel.
It is used with chromium, vanadium, molybdenum, or manganese to produce high speed steel used in cutting tools.
Tungsten steel is said to be "red-hard" or hard enough to cut after it becomes red-hot.
SS321, uses, Titanium for chromium stabilizing.
The biggest advantage of boron is that a small amount can be added to get the same result as other elements required in
large amount in terms of added hardenability. Typical range in steel alloys is 0.0005 to 0.003%.
During the heat treatment process boron, a replacement for other elements, is added to increase the hardenability of
medium carbon steel. The cutting performance for high-speed steels is increased but at the expense of the forging quality. It
is also possible that the content of boron can be too high which decreases hardenability, toughness as well as cause
embrittlement. The percentage carbon present in the steel also plays a role in the hardenability effect of boron. As boron's
effect on hardenability increases, the amount of carbon should proportionally be decreased.
One more reason to add Nickel in alloy, is to create brighter portions in damascus steels. It increases Elastic modulus.
SS 200 series stainless steels, use nitrogen and manganese, to replace costly Nickel.
Ti is a very strong, very lightweight metal that can be used alone or alloyed with steels. It is added to steel to give them high
strength at high temperatures. Modern jet engines use titanium steels.
Nickel is often used in combination with other alloying elements, especially chromium and molybdenum. Stainless steels
contain between 8% and 14% nickel. Low temperature service steels contains nickel as nickel improves impact strength.
After heat treatment the steel maintains its hardness at high temperature making it particularly suitable for cutting tools.
Tungsten in the form of tungsten carbide, (1). Gives steel high hardness even at red heats, (2). Promotes fine grains, (3).
Resists heat, (4). Promote strength at elevated temperatures
Increases hardness, also allows for higher quenching temperatures (during the heat treatment procedure). Intensifies the
individual effects of other elements in more complex steels. Co is not a carbide former, however adding Cobalt to the alloy
allows for higher attainable hardness and higher red hot hardness.
Molybdenum has effects similar to manganese and vanadium, and is often used in combination with one or the other. This
element is a strong carbide former and is usually present in alloy steels in amounts less than 1%. It increases hardenability
and elevated temperature strength and also improves corrosion resistance as well as increased creep strength. It is added
to stainless steels to increase their resistance to corrosion and is also used in high speed tool steels.
The effects of Vanadium chemical element are similar to those of Mn, Mo, and Cb. When used with other alloying elements
it restricts grain growth, refines grain size, increases hardenability, fracture toughness, and resistance to shock loading.
Softening at high temperatures, fatigue stress and wear resistance are improved. At greater than 0.05% Vanadium, there
may be a tendency for the steel to become embrittled during thermal stress relief treatments.
Vanadium is used in nitriding, heat resisting, tool and spring steels together with other alloying elements.
When boron is added to steel, precaution must be taken to ensure that it does not react with oxygen or nitrogen as the
combination of boron with either one of the two, will make the boron useless.
Niobium is a key grain refining element, as well a strength-enhancing elements in steel production. Niobium is a strong
carbide former and forms very hard, very small, simple carbides. Improves ductility, hardness, wear and corrosion
resistance. Also, refines grain structure. Formerly known as Columbium. SS347, uses, niobium for chromium stabilizing.
The most important effect and the purpose of boron in steel is to drastically improve the hardenability.
Ti is used to control grain size growth, which improves toughness. Also transforms sulfide inclusions form elongated to
globular, improving strength and corrosion resistance as well as toughness and ductility
16

By JGC Annamalai
By JGC Annamalai
Effects of Common Alloying Elements in Steel:
Effects of alloying elements on steel (Properties Enhancement)
Boron (B) : Small amounts substantially increase hardenability. Boron-treated steels will usually contain 0.0005–0.003%
boron. Although boron is effective with low-carbon alloy steels, its effectiveness decreases with increasing carbon
content. Boron is not recommended for steels containing over 0.6% carbon.
Manganese (Mn) : Increases hardenability and is a carbide former (Mn3C) above a threshold value. In constructional
steel alloys, manganese substantially increases the critical cooling rate and therefore facilitates deep hardening.
Nickel (Ni) : Increases hardenability by decreasing the critical cooling rate necessary to produce hardening as a result of
quenching and affects austenite transformation by depressing Ac and Ar critical temperatures. Nickel does not form
carbide structures. When combined with chromium, nickel produces alloy steels with higher elastic ratios, greater
hardenability, higher impact strength, and fatigue resistance than is possible with carbon steels.
Vanadium (V) : Increases strength, hardness, and resistance to shock impact. It retards grain growth permitting higher
quenching temperatures. Vanadium also enhances the red hardness properties of high-speed metal cutting tools and
intensifies the individual effects of other major elements.
Cobalt (Co) : Increases strength and hardness and permits higher quenching temperatures. Cobalt also intensifies the
individual effects of other major elements in more complex steels. Most of the teeths of Earth-Movers has Cobalt Steel.
Aluminum (Al) : A deoxidizer and degasifier, which retards grain growth and is used to control austenitic grain structure.
In nitriding steels, aluminum aids in producing a uniformly hard and strong nitride base when used in amounts 1.00%-
1.25%.
Titanium Columbium or Niobium and Tantalum (Ti, Cb, or Nb, Ta) : All used as stabilizing elements in stainless
steels, each has a high affinity for carbon and forms carbides, which are uniformly dispersed throughout the steel. Thus,
localized depletion of carbon at grain boundaries is prevented.
Lead (Pb) : While not strictly an alloying element, lead is added to improve machining characteristics. It is almost
completely insoluble in steel. Minute lead particles, well dispersed, reduce friction where the cutting edge contacts the
work. The addition of lead also improves chip-breaking formations. Lead is found in Babbit and bearing steels.
Silicon (Si) : A deoxidizer and degasifier, which increases tensile and yield strength, hardness, forgeability, and
magnetic permeability. Motor, transformer core steel laminations have Silicon, up to 6%
Chromium (Cr) : Increases a material’s tensile strength, hardness, hardenability, and toughness. Chromium also
creates resistance to wear, abrasion, corrosion, and scaling at elevated temperatures. Addition of chromium, more than
10.5% to steels makes it Stainless Steels.
Nickel (Ni) : Stabilizes the austenitic structure enhancing mechanical properties and fabrication characteristics. Nickel
increases strength and hardness without sacrificing ductility and toughness. It also increases resistance to corrosion and
scaling at elevated temperatures when introduced in suitable quantities in high-chromium stainless steels. Addition of
min 6.6% Nickel to ferritic stainless steel makes it as Austenitic Stainless Steels.
Molybdenum (Mo) : Increases strength, hardness, hardenability, and toughness, as well as creep resistance and
strength at elevated temperatures. Molybdenum improves machinability, resistance to corrosion, and intensifies the
effects of other alloying elements. In hot-work steels, it increases red-hardness properties.
Tungsten (W) : Increases strength, hardness, and toughness. Tungsten steels have superior hot-working and greater
cutting efficiency at elevated temperatures. Most of the machine cutting tools, has Tungsten Steels
Sulfur (S) : Improves machinability in free-cutting steels, but without sufficient manganese it produces brittleness at red
heat. Sulfur can also decrease weldability, impact toughness, and ductility.
By definition, steel is a combination of iron and carbon. It is alloyed with various elements to improve physical properties and
to produce special properties, such as resistance to corrosion or heat. Specific effects of the addition of such elements are
outlined below:
Carbon (C) : Although carbon is not usually considered as an alloying element, it is the most important constituent of
steel. Carbon raises tensile strength, hardness, resistance to wear and abrasion; it conversely lowers ductility,
toughness, and machinability.
Manganese (Mn) : A deoxidizer and degasifier, which reacts with sulfur to improve forgeability. It increases tensile
strength, hardness, hardenability, and resistance to wear, while decreasing tendency toward soaling and distortion.
Manganese raises the rate of carbon-penetration in carburizing. Mn, Al, Si are used as oxygen killers in furnaces.
Phosphorus (P) : Increases strength and hardness and improves machinability, however, it adds marked brittleness or
cold-shortness to steel.
17

By JGC Annamalai
By JGC Annamalai
Vanadium (V) : Vanadium is a strong carbide-forming element. Increases hardenability and promotes finer grain size.
The presence of vanadium decreases high-temperature grain growth. Vanadium exhibits a secondary hardening effect
upon tempering and increases hardness at elevated temperatures.
Silicon (Si) : Silicon increases the critical temperature by amounts that vary with the carbon content; therefore required
austenitizing temperatures are increased. Silicon is not a carbide former. Provides relatively small increase in
hardenability and strengthens low-alloy steels but primarily used in low concentrations as a potent deoxidizer
Chromium (Cr) : Chromium is a strong carbide former, and in the presence of carbon and iron, chromium forms a
complex series of carbide structures. Complex chromium carbides dissolve in austenite slowly. Chromium greatly
increases hardenability and increases oxidation and corrosion resistance and increases the Ac3 critical temperature. If
sufficient austenitizing times are utilized, chromium provides a substantial improvement in the depth of hardening
because the critical cooling rate is decreased.
Molybdenum (Mo) : Molybdenum increases the Ac3 critical temperature in constructional steels at concentrations of
0.1–0.60% and depending on the molybdenum and carbon content, may form complex carbide structures. Increases
hardenability and is more potent than chromium but often used in combination with nickel and/or chromium. In solid
solution, molybdenum decreases transformation rates, and this increases the depth of hardening.
18

Role of Impurities in Welds and in Castings : (Sulfur, phosphorus etc are called impurities or tramp elements)
AA)
BB)
Impurities & Minor elements, causing Hot Cracking are mostly Sulphur, Phosphorus, Copper, Silicon, Niobium, Boron
 Regardless of the delta ferrite present in the weld metal, multiple thermal cycling (multi-pass, as in repair welding), can
cause fissuring by segregation of impurity elements.
 Welding: Higher Energy Densities (low heat input process like : GTAW, EBW (Electron) and LBW (Laser beam welding
) has decreased the cracking, and cracking resistance was progressively higher.
Phosphorus and Sulfur in Stainless Steel Solidification Cracking :
Crack forming Tendency increases, with increase in the Sulfur & Posphorus Impurities.
Main cause of fissuring is believed to be the result of intergranular liquid films of low melting constituents (melting
points, from 900 to 1200°C) rupturing during the contraction that takes place when the wholly austenitic weld or
casting cools from its melting point(1525 to 1550°C). The 270 to 600°C difference produces tension strains when the
weld/casting is highly restrained. Low melting point impurities / films are weak and so they break.
For Castings: Impurities come from contaminated raw materials(scrap, mold, tools). For Welds: High impurity pipes,
electrodes & shielding gas, environment(air), paint, markers,
Effects of Alloying Elements, Iron & Steel.
Chapter-A8 Stainless Steels - Impurities like Sulfur, Phosphorus, Boron
By JGC Annamalai
19

By JGC Annamalai
Based on the above chart,
(1). Higher the chromium or lower the nickel, the point will be moved to the right and will have no crack.
(2). Even with Creq/Nieq=0.9, and with lower the P+S(<0.01%), there will be no crack.
(3). For 0.01% P+S, there will be no crack, if the Creq/Nieq is 0.9 This means, 8%Ni SS, should have min. 7.2% Cr
(4). With higher P+S, there will be no crack, if Creq/Nieq should be increased
(5). For Creq/Nieq=1.5, P+S should be max. 0.06%. For 18% Cr, Ni should be 12% or less for no crack.
(6). Normally, SS304, has P+S around 0.06%. The Creq/Nieq is 1.56, (Creq=19.625, Ni eq 12.58) .
So, there will be no crack.
Source for Sulfur, Phosphorus : On Castings:
2
On Welding:
1
Harmful Effects of Impurities
Raw Material : Pipes and fittings, plates material may have
contaminations like : grease, oil, painting, galvanizing, paint chalk marks,
plastics or non-metals, wood, cloths etc,
Control P, S in the base material. Please
segregate and remove all contaminating
materials
Impurities like Phosphorus
and sulfur combine with Iron
and Nickel in stainless steel and
form low melting point Eutectics
and stay as liquid, even after
majority of stainless steel had
solidified. They stay as films on
the grain boundries, and will
have weak bond. Contracting
stresses and outside pulls, will
break the bond and initiate
cracking. It is said, Sulfur
absorbs, Cr in the Passive
Layer & weakens it.
Titanium (SS321), Niobium
(SS347) are in stainless steel
for stabilizing purpose. Boron,
silicon etc are added for
special purpose. They form low
melting compounds with Iron,
Nickel and Carbon in Stainless
Steels and behave like
impurities and later form
cracks. So, need of Ti, Nb, B, Si
should be checked & need
care.
2 Electrodes, may have excess P, S, Si. Electrodes may be contaminated
and not stored in electrode box or in the oven. Edges contaminated
Control P, S in the Electrodes. Weld: Clean
the edges and base metal, up to 20 mm
from fusion line
1 Raw material may have contaminations like : oil, paint, grease,
galvanizing, or chalk marks, plastics or non-metals, wood, cloths, soap
etc,
Please segregate and remove all
contaminating materials
Raw material may have high sulfur and phosphorus in the chemical
analysis
Specify low S, P in the raw material
Contaminations Counter Measures
Brittleness: The lack of ductility (high brittleness) at high temperatures near the solidus is usually due to the formation of
an intergranular liquid film of an impurity, notably sulfur and phosphorus in metal. Both these impurities combine with the
matrix elements to form low-melting-point (lower than that of the matrix) compounds, thereby reducing intergranular
cohesion. The lack of cohesion between grain boundaries, in turn, initiates cracks aided by tensile stresses resulting from
the contraction of the weld or cast metal.
20

By JGC Annamalai
Harmful Effect of Individual Elements, like Sulfur, Phosphorus during solidification of Castings and Welds :
(1)
(2)
(3)
(4)
Recommended optimum values for boron content are from 0.0025 to 0.006%.
In Austenitic solidification mode of 310 and 304 SS, sulfide films were
present even with 0.005%S and these films increased the brittleness
(1). Hull in Stainless Steels
(2). Borland & Younger in Steels.
temperature range along with phosphorous. Preferred level to control crack, max. sulfur in Austinitic , 0.005%
Phosphorus : Like sulfur, P forms low melting eutectics with, iron,
chromium and nickel. The maximum solubility of P (a). in austenite at
the eutectic point (1150°C) with iron is 0.25% and (b). in ferrite at
1050°C is 2.8%. Phosphide eutectics at interdendritic regions have been
found to lower the brittleness temperature range to as much as 250°C
lower than the solidus in fully austenitic type 310 steel. The segregation
tendency remains high due to the wide solid-liquid range and low
eutectic temperatures (1100°C ) . The low diffusivity of P in both
austenite and ferrite phases even at high temperatures virtually
precludes homogenization. Liquation cracking in Alloy 800 welds
containing 0.4% titanium, found enrichment of phosphorous on the weld
HAZ crack surfaces up to 10 times the matrix content even when
present at a level as low as 0.01 %P. Preferred level to control crack,
max. sulfur in Austinitic , is 0.005%
Fully austenitic stainless steels (like SS310) are prone to hot cracking. To avoid cracking in Aus SS, segregation
causing phosphorus and sulfur, both(separately) should be restricted to less than 0.002%.
P + S: For Cr/Ni equivalent ratios below 1.5, fully austenitic solidification occurs and crack lengths above
2.5mm were found for P+S greater than 0.15%. Titanium containing 15Cr-15Ni stainless steel found grain boundary
precipitates of titanium carbosulfide which decreased the hot ductility in the temperature range 1100-1300°C. Sulfur
enrichment up to 2000 times were noticed at weld HAZ cracks in type 310 stainless steel.
Control : Steel Mill : To meet ASTM and Spec control, impurities like Sulfur, Phosphorus and excess carbon are
removed in the ladle hot liquid metal of iron, steel or stainless steels, using oxygen or oxygen-argon lance
It is recommended that for fully austenitic stainless steels, the maximum of 0.005%S and 0.006%P must be used to
avoid solidification / fusion zone cracking.
Boron is considered (1). good for health, (2). absorbs Neutrons in nuclear reactors, (3). to make tough glass and
fiberglass etc. In ferrous Metallurgy, Boron is like phosphorus and sulfur and forms low melting eutectics in iron and
nickel systems. Boron(soluble 3.8% in Iron) forms a low melting eutectic at 1411°C. The solubility in austenite at this
temperature is only 0.021% and decreases rapidly to become negligible at 773°C and lower. The decrease is
accompanied by the precipitation of brittle iron and nickel borides.
Boron is considered as one of the most damaging elements to hot cracking. Liquation crack was found in the weld
HAZ when the boron content was greater than 0.001% in Type 321 stainless steels. Boron is very effective in
improving creep properties of stainless steels. Boron up to 0.005% is considered desirable for high temperature
applications. Close control of boron is necessary for good weldability, creep properties etc.
Due to extreme hardness at high temperatures, boron is used as surface hardner, in Automobile Industries for wear
resistance. It gives much longer service life compared to functional surfaces compared to nitriding, carburizing,
chrome plating, thermal spraying, CVD or PVD coating. Boriding (boronizing) is a thermochemical diffusion process in
which hard and wear resistant boride layers are generated by diffusing boron onto the surface of material at 750 to
950°C.
As early as 1960, Hot Cracking Tendency
due to Impurities and Minor Elements was
studied by :
In the ferritic solidification mode, no sulfur hot cracks were found till S is
0.05%. 304 SS with delta ferritic solidification mode, a sulfur content of
0.2% produced a low melting sulfide eutectic at 1280-1410 °C and
without hot cracks .
Sulfur : Known to be undesirable impurity in welding and casting of
stainless steels due to the formation of low melting sulfide films along
the inter-dendritic and grain boundary regions. Sulfur is almost insoluble
in all three major constituents of stainless steel viz. iron, chromium and
nickel.
Sulfur is strongly rejected into the liquid during solidification of austenite,
rapidly lowering the melting point of the inter-dendritic liquid. Thus the
potential for sulfur(even, S<0.005%) forming low melting eutectics
remains strong. Sulfur impurity, Ni-NiS has melting point as low as
630°C. High content of sulfur is in the last liquid to solidify. The
solidification crack surfaces are highly enriched in sulfur. The
segregation ratio between the top atom layer and the bulk metal was
about 2000. On the other hand, delta ferrite shows higher solubility for
elements like S, P, Si and Nb.
21

Chapter-A9
Here, we study the changes in the gamma loop & Eutectoid Point while alloying with different elements.
Gamma loop or the austenite region in the iron-carbon diagram is the impartant zone, where the phase change is taking
place. The steels are heated to "γ" region(for forging, rolling, drawing, normalizing, annealing, quinch and tempering) and
for major heat treatments
Effect of Alloying Elements, Iron & Steel.
Iron and Carbon diagram is considered simplest phase diagram. Steel is mostly used in the group, particularly carbon
from 0 to 1.6%.
(a). For jobs involving welding , where no crack, ductile, low hardness are required, carbon less than 0.2% is preferred.
However, mild steel or low carbon with carbon 0.35% or carbon equivalent 0.4% is considered max. for good weldability.
(b). For jobs involving higher hardness, with high strength, less ductile carbon 0.4 to 1.6% is commonly used. These steels
are used where high hardness and high strengths are required. These steels undergo heat treatment to enhance hardness
and strength etc.
(c). Straight carbon steels does not meet strength requirements, in some cases. So, alloys of other elements are added to
improve the steel strength, corrosion resistance, higher impact properties, wear resistance etc.
Effect of Alloying Elements on Iron-Carbon Diagram, γ Loop
By JGC Annamalai
22

Chapter-A9 Effect of Alloying Elements on Iron-Carbon Diagram, γ Loop
By JGC Annamalai
Iron-Chromium, Phase Diagram Iron-Nickel Phase Diagram
Effect of Various Elements, on the Gamma loop of Iron-Carbon Diagram
18% Stainless Steel, with different Ni % ; Carbon Vs Temperature, phase changes
Austenitic stainless steels cannot be hardened via heat treatment. Quenching does not harden ASS. Instead, these steels
work harden (they attain hardness during their manufacture and formation). Annealing(solution annealing) these stainless
steels softens them, adds ductility and imparts improved corrosion resistance. Welding : preheat and PWHT are
not required.
23

Chapter-B1
Spectrometers :
Uses of Spectrometers / Metal Analyzers:
After the attack on World Trade Center, in Sep 11, 2001, Authorities started to use more
spectrometers to detect the weapons and explosives in solid / plastics, liquid, gas forms.
The security was tightened, in the Airports, Ship Ports, Train and Bus Stations,
Offices and other suspected places.
General : Process Control and Monitoring; Indentification of Chemical Compounds, Medical Diagnostics; Chemical
Analysis; Material and Polymer Analysis; Raman Spectroscopy; Color Measurements; Environmental Monitoring;
Authentication and Anti-Counterfeiting; Light Measurements; Quality Control; Water Quality Analysis; History and
archeology; Food analysis for Heavy metals; pharmaceutical; Security check; Fire or smoke detection/alarm;
Inner-workings of a spectrometer , the components working etc. are designed to achieve a
desired outcome, Touch on facility on some of the accessories are also available.
Once the light is imaged onto the detector the photons are then converted into electrons
which are digitized and read out through a USB (or serial port) to a computer. The
software then interpolates the signal based on the number of pixels in the detector and the
linear dispersion of the diffraction grating to create a calibration that enables the data to be
plotted as a function of wavelength over the given spectral range. This data can then be
used and manipulated for countless spectroscopic applications,
The basic function of a spectrometer is to take in light, break it into its spectral components, digitize the signal as a
function of wavelength, and read it out and display it through a computer. The first step in this process is to direct light
through a fiber optic cable into the spectrometer through a narrow aperture known as an entrance slit. The slit
vignettes the light as it enters the spectrometer. In most spectrometers, the divergent light is then collimated by a
concave mirror and directed onto a grating. The grating then disperses the spectral components of the light at slightly
varying angles, which is then focused by a second concave mirror and imaged onto the detector. Alternatively, a
concave holographic grating can be used to perform all three of these functions simultaneously. This alternative has
various advantages and disadvantages,
Raman had invented a type of spectrograph for detecting and measuring electromagnetic waves. Raman spectroscopy
is a spectroscopic technique typically used to determine vibrational modes of molecules, although rotational and other
low-frequency modes of systems may also be observed. Raman spectroscopy is commonly used in chemistry/analysis
to provide a structural fingerprint by which molecules of materials can be identified..
Effect of Alloying Elements, in Iron & Steel
Over the past 20 years, miniature fiber optic spectrometers have evolved from a novelty to the spectrometer of choice
for many modern spectroscopists. People are realizing the advanced utility and flexibility provided by their small size and
compatibility with a plethora of sampling accessories.
A spectrometer is a scientific instrument used to
separate and measure spectral components of a
physical phenomenon. Spectrometer is a broad
term often used to describe instruments that
measure a continuous variable of a phenomenon
(light radiation etc) where the spectral
components are somehow mixed. ...
A mass spectrometer measures the spectrum of
the masses of the atoms or molecules present in
a gas. The first spectrometers were used to split
light into an array of separate colors.
Spectrometers
Raman received the 1930 Nobel Prize in Physics for the discovery and was the first Asian to receive a Nobel Prize in any
branch of science.
Sir Chandrasekhara Venkata Raman (Sir
C.V.Raman) (7 November 1888 – 21 November
1970) was an Indian physicist known for his work
in the field of light scattering. Using a
spectrograph that he developed, he and his
student K. S. Krishnan discovered that when light
traverses a transparent material, the deflected
light changes its wavelength and frequency. This
phenomenon, a hitherto unknown type of
scattering of light, which they called "modified
scattering" was subsequently termed the Raman
effect or Raman scattering.
By JGC Annamalai
24

Chapter-B2
Developments :
PMI, Positive Material Identification or Inspection
Alloy Element Detection & Analysis (PMI Testing )
PMI : The selected material is checked at the source of supply and moved to the Fabrication or to the Site. However, to
have consistant quality and to prevent lapses, material mix up, before start of fabrication and/or assembly, the material
used at the Fab.shop or at the Site are often checked for the traceability of the material whether specified and correct
material is used and there is no wrong material is used. It is called Positive Material Inspection or Identification.
Often Design Engineers and Material Engineers of critical Industries (Nuclear, Space Research, Power Plant, Oil &
Gas, Chemical, etc). select and decide the best metal for the fluid handled or for the environment, considering strength,
high and low temperature use, pressure, corrosion,cryo and other loads like fatiue, rotational, etc. Material data are
specified in ASTM, AISI/SAE, API, etc standards and Users specification.
Need of Positive Material Idenfication(PMI) and Analysing :
Earlier to 1980, Plant Operaters found frequent burst of equipments and piping and fire accidents, in their plants. Cause
: material mixing up, non-spec material supply, etc.
Many plants and their vendors used, minimal check on materials, like random check on materials, by color, weight,
shining etc. Their MTC or MTR or lab reports were checked. Later chemical analysis, by lab itiration methods, was used
to check material requirement and their elements. It was time consuming.
Around 1983, Portable metal analyers, with radio isotopes, were used. They worked on "X-ray Diffraction or
Fluoracence" principle, was introduced by Texas Nuclear. They were used to identify mostly Cr, Ni, Mo only and their
percentages. With new technology, instrumentation etc, additional elements were identified/quantified. However, some
alloy elements , like Oxygen, Nitrogen, Carbon, Sulfur etc were not detected and/or no % checked. From 2000, Spark
and optical emission Spectroscopy are used to find most of the elements of alloys in the Periodic Table (metals and non
metals).
By JGC Annamalai
25

Chapter-B2 Alloy Element Detection & Analysis (PMI Testing )
By JGC Annamalai
Advantages of using PMI :




 Failure Analysis PMI – it is vital that the cause is identified and
resolved to avoid repeat failures
 Ensure compliance with local government and legal requirements
 Reduce risk of company liability with documented safety standards
Some Definitions :
Major Functions of PMI :
(1). Verify alloying elements and other metals in seconds.
(2). Enhance material traceability. To avoid metal/material mix-up.
(3). Confirm the integrity of plant equipment and materials, whether the supplied materials is per P.O. requirements.
Arc : Common: Part of a curve or circle. Electric: Continuous flow or stream of charged sparks, as in arc welding.
Positive material identification (PMI) is an essential non-destructive testing (NDT) method utilized to verify that
supplied materials conform to the proper standards and specifications. Specifically, PMI is used to confirm that the
chemical composition of the metallic parts has the correct percentage of key elements, this ensures that material
properties such as corrosion resistance meets the requirements and the material meets, the specified standards and
specifications.
PMI is a widely adopted as non-destructive testing method and there are
several standards and recommended practices for it.
The following API and ASTM documents cover the use of the handheld
XRF and other applicable techniques.
API RP 578 – Material Verification Program for New and Existing Alloy
Piping Systems, - guidelines for a quality assurance system to verify the
alloy components.
Diffractometers : - used to measure crystal structure, grain size, texture,
and/or residual stress of materials and compounds through the
interaction of X-ray beams, gamma rays, electron beams, or neutron
beams with a sample
Security System Services :- checks in Airport, protected area,
courthouses, jails etc. Scan or take picture of whole body, using portable
or hand-held X-ray systems and X-ray generators. computed
radiographic (CR) systems, digital radiographic
Spark : Common: an ignited or fiery particle such as is thrown off by
burning wood or produced by one hard body striking as lighter and
grinderagainst another. Electric : short discharge between poles
ASTM E1476 - Standard Guide for Metals Identification, Grade
Verification, and Sorting.
X-ray Instruments and X-ray Systems : - use material penetrating X-
rays or gamma radiation to capture images of the internal structure of a
part or finished product. They are mostly portable (also called handheld
or mobile)
Ensure that products and components have been manufactured
using the correct alloy
Ensure material conforms to the correct standard and specification
Ensure welded components have used the correct filler material
X-ray sources : - lamps that generate or produce X-rays, a form of
electromagnetic radiation, for non-destructive testing (NDT) or inspection
Find knowingly or unknowingly mixed-up alloys
X-ray fluorescence spectrometers (XRFs) : - portable, use a
spectroscopic technique that is commonly used with solids, in which X-
rays are used to excite a sample and generate secondary X-rays.
Positive Material Identification (PMI) : Driven by Country and / or Company regulations and as a result of material mix-
ups, mis-labelled shipments and industrial accidents, companies are increasingly relying on analysis quickly and
accurately to determine the chemical composition of materials and alloys. Positive Material Identification (PMI) testing
has established itself as a solution for ensuring product quality, a safe manufacturing environment and quick results.
Uses of Spectroscope : for research in metallurgy, forensics, polymers, electronics, archaeology, environmental
analysis, geology, mining, pharmaceutics, chemistry, biology, and medicine – in fact any research requiring non-
destructive high sensitivity elemental micro analysis and imaging.
26

By JGC Annamalai
The most predominant techniques for Elemental Analysis are :
1) Fluorescence Spectrometry (AES/AFS)
2) Inductively Coupled Plasma Mass Spectrometry (ICP-MS)
3) Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES)
4) Neutron Activation Analysis (NAA)
5) X-Ray Fluorescence (XRF)
6) Anodic Striping Voltammetry (AVS)
1. Thermo Fisher 4. Shimadzu
Suppliers 2. Hitachi High Tech 5. Texas Nuclear
3. Bruker
These are 3 Popular Technologies for Element Detection, Analysis and quantifying the Elements, in Alloys :
(1). X-ray Fluorescence (XRF) also called Atomic Fluorescence (ARF), X-ray Diffraction (XRD)
(2). Optical Emission Spectrometry (OES),
(3). Laser Induced Breakdown Spectroscopy (LIBS)
(1). X-ray Fluorescence (XRF)
(2). Optical Emission Spectrometry (OES),
XRF or XRD : This method was first proposed by Glocker and Schreiber in 1928.
Earlier years, most of the metal or element detection instruments, were very large in size and carried in large boxes or
moved in a cart. Due to the advent and development of systems and instruments, the size of the test apparatus were
shrunk and now they are mostly handheld or carried in a compact box. Some of the detectors now weigh about 1 kg.
Popular Element Analyzer
Brands:
XRF is suitable for solids, liquids and powders,
and in most circumstances, it is NDT
WDXRF can find from beryllium (Be) to
Uranium (U), more low denser elements)
Primary X-rays are generated by the source and directed at the sample’s surface. When the beam hits the atoms in the
sample, they react by generating secondary X-rays that are collected and processed by a detector. Today, the method is
used as a non-destructive analytical technique, and as a process control tool in many extractive and processing
industries. In principle, the lightest element that can be analysed/detected is Beryllium (Z = 4), but due to instrumental
limitations and low X-ray yields for the light elements, it is often difficult to quantify elements lighter than Sodium (Z =
11), unless background corrections and very comprehensive inter-element corrections are made. For improvement,
Vacuum(around 10 Pa residual pressure, 0.075 torr) or Argon or Helium purging is used, instead of air medium at the X-
ray port.
EDXRF can find all elements from sodium
(Na) to uranium (U),
27

By JGC Annamalai
(3). Laser Induced Breakdown Spectroscopy (LIBS)
Chemical Analysis Method:
New Developments :
Since the advent of Chemistry, lab technicians identify and quantity elements of materials with which they are working,
by Titration. Consequently, the development of chemical analysis parallels the development of Chemistry. The 18th
century Swedish scientist, Torbern Bergman is usually regarded as the Founder of inorganic qualitative and quantitative
chemical analysis. Prior to 20th century, nearly all analysis of materials were performed by classical methods. Although
simple instruments (such as photometers and electrogravimetric analysis apparatus) were available at the end of the
19th century, instrumental analysis did not flourish until 20th century. The development of electronics during World War
II and subsequent widespread availability of digital computers have hastened the change from classical to instrumental
analysis in most laboratories. Although most metal analysis, currently are performed instrumentally, there remains a
need for some classical analysis.
XRF, OES and LIBS and beyond : Scientist and Engineers are continuously working to widen the scope of these
instruments and to use in many engineering, medical and biological deciplines. These new searches and instruments
are Invaluable for research in forensic science, pharmaceutics, electronics, geology, archaeology, metallurgy, chemistry,
biology, and medicine – in fact any research requiring non-destructive high sensitivity elemental microanalysis and
imaging.
The present instruments are mostly for macro studies. Using very fine X-ray beams, the instruments can detect and take
pictures of grains, to the accuracy of 10μm
A high-power laser pulse is used as an energy source to
cause ablation(Ablation is removal or destruction of
something from an object by vaporization, chipping,
erosive processes) of atoms from the sample surface
and formation of a short-lived, high-temperature plasma.
Plasma temperatures are generally hotter than 10,000 K
with sufficient energy to cause excitation of electrons in
outer orbitals. As the plasma cools, the excited electrons
decay to lower-energy orbitals, emitting photons with
wavelengths inversely proportional to the energy
difference between the excited and base orbitals. There
are many possible excited states and thus many emitted
wavelengths for each element.
A range of Nd : YAG (neodymium-doped yttrium
aluminum garnet; Nd:Y3Al5O12), is a crystal and is used
in lasers
in analysis of elements in the
periodic table. Though the
application by itself is fairly
new with respect to
conventional methods such
as XRF or ICP, it has proven
to be less time consuming
and a cheaper option to test
Arc or Spark : With OES, the energy used to excite the
molecules in the sample is electricity; there are two forms of
electrical discharge generated – an arc, which is an on/off
event similar to a lightning strike, or a spark, a series of multi-
discharge events where the voltage of the electrode is switched
on and off. Light is the source of detection and measurement.
Although OES analysis can only be carried out on metals, that
doesn’t mean it can’t measure non-metallic elements. In fact,
OES gives superior performance when measuring carbon,
boron, phosphorous and nitrogen in steel. OES devices offer
the highest levels of accuracy, with very low levels of detection
for all the important elements. However, the electric energy will leave a burn mark on the sample. OES devices use
more energy than LIBS or XRF and also require argon gas canisters unless using an arc probe.
28

Chapter-B3
Property XRF OES LIBS
Source of
Detection
X-Ray hits the atoms and produces secondary
X-Ray
Arc or Spark, produces light from
elements
Laser ablates the elements and light is
emited from elements.
Working
Principle
XRF(X-Ray Fluorescence) is the most
commonly used Non-Destructive Test (NDT)
method offering the user a portable handheld
analyzer that delivers fast, accurate results.
Handheld XRF analyzers use an x-ray tube to
emit an x-ray beam into a sample, exciting the
electrons and displacing them from the inner
shell. The vacancy from the inner shell then
gets replaced with an electron from an outer
shell. As this electron fills the vacancy of the
inner shell it releases energy in the form of a
secondary X-ray. This release of secondary
energy is known as fluorescence.
OES(Optical Emission Spectroscopy)
involves applying electrical arc energy
generated between the electrode and
metal sample in an argon atmosphere.
Vaporized atoms are brought to a high
energy state and light is emitted. High
energy promotes the atoms into excited
electronic states that subsequently emit
light when they return to the ground
electron state. The excited atoms and ions
of each element have a characteristic
emission spectral line. The light channels
through photo multiplying detectors and
measure the presence and intensity of
each element
LIBS(Laser-Induced Breakdown
Spectroscopy) is a type of atomic emission
spectroscopy that employs a laser to ablate
or vaporize a microscopic layer of a
sample’s surface. The resultant plasma
caused by this laser ablation process emits
light as it cools. Each element emits light
at a characteristic wavelength, which is
isolated by a grating and detected via a
spectrometer.This light is then collected and
analyzed with a spectrometer for
quantitative and qualitative material
/element analysis
Time / Speed Normally require 5 minutes for 6 samples.
Each test require about 15 seconds for
analysis.
Within 30 Seconds
It’s very fast – a test can be carried out in
just one second.
Location of
Test
Portable & hand-held. The test can be
conducted on the job or at Site.
Determining
Impurities
Normally 10 elements are determined. Mostly
impurities will be covered in the 10 elements.
OES is superior when measuring carbon,
boron, phosphorous and nitrogen in steel
Can also measure : H2, He, Li, Be, B, C, N2,
O2, F2, Ne, Na.
Accuracy There is no weighing, volume measurement,
so % error is reduced. Accuracy range
obtained is about 0.1%
Versatile and reliable for general metal
element analysis/PMI. Highest levels of
accuracy, with very Low Levels of
detection.
Versatile and reliable for general metal
element analysis/PMI.
Sample
volume and
location area
Actual objects can be taken for element
determination. The area of arcing/charred
location is about 1 or 2 mm dia(some are as
low as 10 µm). Often PMI procedures ignore
such tiny surface damage.
Used since say from 1980 New and Very latest
Dedicated test speciments
are prepared
Compare Chemical Analysis, XRF, OES, LIBS PMI - Metal Analyzers
Wet method. Normally
require, 2 days for 6 samples
The test samples are
prepared and tested in the
Lab
Due to time limitation,
determining level of impurites
is often overlooked.
Weighing, volume
measurement, transferring
etc jobs reduce the % of
accuracy.
Traditional
Chemical Analysis Method
Old and Traditional method.
Samples are either in the
chip or powder form, often
dissolved in some solutions.
The solutions are titrated.
The Chemistry Lab
Technicians identify the
elements,and quantify the
elements of the alloy
materials
29

Property XRF OES LIBS
Chemical Analysis Method
Merits Can Analyze, when samples are hot,
conductive and non-conductive substances,
metals and non-metals, in granular and liquid
forms(like soil and fuel oil).
Analyze most elements in the Periodic
Table, sometimes non-metallic elements.
It’s very fast – a test can be carried
out in just one second. Analyze/
measure light elements.
Limitations Radiation;
Light elements((H2, He, Li, Be, B, C, N2, O2,
F2, Ne, Na).analysis with handheld XRF can
be challenging because the secondary/
fluorescent X-rays from lighter elements
(Z<18) are less energetic and are greatly
attenuated as the X-rays pass through air.
Also, sample preparation is highly
recommended. It is difficult to distinguish
SS316 and SS316L or 316H.
High electrical energy. The electric(arc or
spark) energy will leave a burn mark on
the sample. OES uses more energy than
LIBS or XRF and also require argon gas
for shielding the arc or spark. Surface
needs, mechanical sanding before the test
and removal of the surface burn, after the
completion of the test
Samples can be conductive or non-
conductive but need to have a solid surface
that is clear of dirt and contaminants before
testing. LIBS will leave a small laser burn on
the sample. Argon is needed to analyze
carbon. Sample preparation is required for
analysis.
Weight 3 kg 50kg(processor-25kg, Argon-20kg+ cart,
gun-3kg)
3kg
Avg.₹ 2000000 / Pc (Rs.400000 to 3600000)
Avg.$.27000
Light Elements: Neon, Sodium, Magnesium, Aluminum, Silicon, Phosphorus, Sulfur
Extra Light Elements: Hydrogen, Helium, Lithium, Beryllium, Boron, Carbon, Nitrogen,
Oxygen, Fluorine
The system is bulky and difficult to transport to elevated places at the Site.
Requires argon gas for accurate results. Requires large battery power
Very Quick detection and analyzing.
Unit is light weight and compact and handheld
Can also measure : H2, He, Li, Be, B, C, N2, O2, F2, Ne, Na.
Significant surface preparation is required ; A burn mark is left on the material
Cost
Need extra preparation on the test surface. Have burn marks on laser affected surface
Requires Argon shielding to the Laser, during carbon analysis
Very little surface preparation is required on the sample
Can sample small pieces of material such as wire
Can also measure : H2, He, Li, Be, B, C, N2, O2, F2, Ne, Na.
Advantages
LIBS
XRF
OES
Widely used. The unit is light and easy to use
Disadvantages
Can only measure a few hundred microns into the surface of the sample for light alloys
and a few tens of microns for heavier alloys
All(light Metal) elements can not be detected with this technique
Most popular. Mostly at room
temperature, can be in
solids, in powder or chip
forms.
Time consumption,
sometime, 2 days to wait.
30

Chapter-B4
Features to look for when purchasing a hand held metal analyzer.
1. Analytical Range. Ensure that the analyzer can measure key elements, such as carbon (C).
2. Repeatability. Variances in measurements will result in irregularities of finished goods. By verifying repeatability,
we can guarantee the quality of your processes
3. Lightweight. Fatigue is likely to set in sooner with instruments weighing over 7 pounds(3,2 kg).
4. Hot Swap Battery. Reduce downtime with a hot swap battery when power is depleted.
5. Cameras. A micro camera can precisely pinpoint your exact measurement, while a macro camera can collect
sample imagery.
6. Miniaturized Geometry. Evaluate whether you’ll be able to access tight welds, corners, and joints.
8. WiFi Connectivity. Off-site workers may need access to key analytical information. Determine if you’ll be able to
obtain data with WiFi connectivity.
9. Easy Navigation. A tilting, color touchscreen and directional keys make it easy for users to navigate through
menus and sample readings. Ensure that touchscreens can also be operated with gloves on.
10. Splash/ Dust proof. Look for a minimum rating of IP54 to ensure splash and dustproof claims are validated.
11. Explore Training
XRF & LIBS Safety Training
Radiation Detection User Training
7. Safety Interlocks. Check for multiple robust laser safety interlocks to ensure that users are protected during
operation.
Effect of Alloying Elements, in Iron & Steel
Checklist of Features of Analyzers / Spectrometers
31
By JGC Annamalai

Chapter-B5a
Atomic
Number
Chemical
Element Name
Symbo
l
Atomic
Weight
Specific
Gravity
Melting
Point, °C
Boiling
Point, °C
No. of
Isotope
s
Discoverer Year
1 Hydrogen H 1.00794 0.0705 -259.34 -252.87 3 Cavendish 1766
2 Helium He 4.0026 0.17855 -272.2 -268.93 5 Janssen 1868
3 Lithium Li 6.941 0.534 180.5 1342 5 Arfvedson 1817
4 Beryllium Be 9.01218 1.848 1287 2471 6 Vauquelin 1798
5 Boron B 10.811 2.377 2075 4000 6 Gay-Lussac and Davy 1808
6 Carbon C 12.0107 1.8?3.58 4492 (G) 3825 7 Prehistoric ?
7 Nitrogen N 14.0067 0.8085 -210 -195.79 8 Rutherford 1772
8 Oxygen O 15.9994 1.145 -218.79 -182.95 8 Priestley/Scheele 1774
9 Fluorine F 18.9984 1.1085 -219.67 -188.12 6 Moissan 1886
10 Neon Ne 20.1797 0.8999 -248.59 -246.08 8 Ramsay and Travers 1898
11 Sodium Na 22.9898 0.971 97.8 883 7 Davy 1807
12 Magnesium Mg 24.305 1.738 650 1090 8 Black 1755
13 Aluminum Al 26.9815 2.6989 660.32 2519 8 Whler 1827
14 Silicon Si 28.0855 2.33 1414 3265 8 Berzelius 1824
15 Phosphorous P 30.9738 1.82 44.15 280.5 7 Brand 1669
16 Sulfur S 32.065 2.071 95.3 444.6 10 Prehistoric ?
17 Chlorine Cl 35.453 1.565 -101.5 -34.04 11 Scheele 1774
18 Argon Ar 39.948 1.78375 -189.35 -185.85 8 Rayleigh and Ramsay 1894
19 Potassium K 39.0983 0.862 63.5 759 10 Davy 1807
20 Calcium Ca 40.078 1.55 842 1484 14 Davy 1808
21 Scandium Sc 44.9559 2.989 1541 2836 15 Nilson 1878
22 Titanium Ti 47.867 4.55 1668 3287 9 Gregor 1791
23 Vanadium V 50.9415 6.11 1910 3407 9 del Rio 1801
24 Chromium Cr 51.9961 7.18-7.20 1907 2671 9 Vauquelin 1797
25 Manganese Mn 54.938 7.21745 1246 2061 11
Gahn, Scheele, and
Bergman
1774
26 Iron Fe 55.845 7.894 1538 2861 10 Prehistoric ?
27 Cobalt Co 58.9332 8.9 1495 2927 14 Brandt
c.173
5
28 Nickel Ni 58.6934 8.902 1455 2913 11 Cronstedt 1751
29 Copper Cu 63.546 8.96 1084.62 2562 11 Prehistoric ?
30 Zinc Zn 65.39 7.133 419.5 907 15 Prehistoric ?
31 Gallium Ga 69.723 5.904 29.76 2204 14 de Boisbaudran 1875
32 Germanium Ge 72.64 5.323 938.25 2833 17 Winkler 1886
33 Arsenic (gray) As 74.9216 5.73 817 603 14 Albertus Magnus 1250
34 Selenium Se 78.96 4.79 220.5 685 20 Berzelius 1817
35 Bromine Br 79.904 3.125 -7.2 58.8 19 Balard 1826
36 Krypton Kr 83.8 3.7335 -157.38 -153.22 23 Ramsay and Travers 1898
37 Rubidium Rb 85.4678 1.532 39.3 688 20 Bunsen and Kirchoff 1861
38 Strontium Sr 87.62 2.54 777 1382 18 Davy 1808
39 Yttrium Y 88.9059 4.457 1522 3345 21 Gadolin 1794
40 Zirconium Zr 91.224 6.5063 1855 4409 20 Klaproth 1789
41 Niobium/Columbiu
m
Nb 92.9064 8.57 2477 4744 24 Hatchett 1801
42 Molybdenum Mo 95.94 10.22 2623 4639 20 Scheele 1778
43 Technetium Tc 982 11.503 2157 4265 23 Perrier and Segr 1937
44 Ruthenium Ru 101.07 12.44 2334 4150 16 Klaus 1844
45 Rhodium Rh 102.906 12.41 1964 3695 20 Wollaston 1803
46 Palladium Pd 106.42 12.02 1554.9 2963 21 Wollaston 1803
47 Silver Ag 107.868 10.5 961.78 2162 27 Prehistoric ?
Properties of Elements / Atoms :
Light
Elements
Extra-Light
Elements By JGC Annamalai
32

Atomic
Number
Chemical
Element Name
Symbo
l
Atomic
Weight
Specific
Gravity
Melting
Point, °C
Boiling
Point, °C
No. of
Isotope
s
Discoverer Year
By JGC Annamalai
48 Cadmium Cd 112.411 8.65 321.07 767 22 Stromeyer 1817
49 Indium In 114.818 7.31 156.6 2072 34 Reich and Richter 1863
50 Tin (white) Sn 118.71 7.31 231.93 2602 28 Prehistoric ?
51 Antimony Sb 121.76 6.61 630.63 1587 29 Early historic times ?
52 Tellurium Te 127.6 6.24 449.51 988 29 von Reichenstein 1782
53 Iodine I 126.904 4.93 113.7 184.4 24 Courtois 1811
54 Xenon Xe 131.293 3.525 -111.79 -108.12 31 Ramsay and Travers 1898
55 Cesium Cs 132.905 1.873 28.5 671 22 Bunsen and Kirchoff 1860
56 Barium Ba 137.327 3.5 727 1897 25 Davy 1808
57 Lanthanum La 138.906 6.166 918 3464 19 Mosander 1839
58 Cerium Ce 140.116 6.771 798 3443 19 Berzelius, Hisinger,
Klaproth
1803
59 Praseodymium Pr 140.908 6.772 931 3520 15 von Welsbach 1885
60 Neodymium Nd 144.24 6.8 1021 3074 16 von Welsbach 1885
61 Promethium Pm 1452 ? 1042 3000 14 Marinsky et al. 1945
62 Samarium Sm 150.36 7.536 1074 1794 17 Boisbaudran 1879
63 Europium Eu 151.964 5.283 822 1529 21 Demarcay 1901
64 Gadolinium Gd 157.25 7.898 1313 3273 17 de Marignac 1880
65 Terbium Tb 158.925 8.234 1356 3230 24 Mosander 1843
66 Dysprosium Dy 162.5 8.54 1412 2567 21 de Boisbaudran 1886
67 Holmium Ho 164.93 8.781 1474 2700 29 Delafontaine and Soret 1878
68 Erbium Er 167.259 9.045 1529 2868 16 Mosander 1843
69 Thulium Tm 168.934 9.314 1545 1950 18 Cleve 1879
70 Ytterbium Yb 173.04 6.972 819 1196 16 Marignac 1878
71 Lutetium Lu 174.967 9.835 1663 3402 22 Urbain/ von Welsbach 1907
72 Hafnium Hf 178.49 13.31 2233 4603 17 Coster and von Hevesy 1923
73 Tantalum Ta 180.948 16.654 3017 5458 19 Ekeberg 1801
74 Tungsten W 183.84 19.3 3422 5555 22 J. and F. d'Elhuyar 1783
75 Rhenium Re 186.207 21.02 3186 5596 21 Noddack, Berg, Tacke 1925
76 Osmium Os 190.23 22.57 3033 5012 19 Tennant 1803
77 Iridium Ir 192.217 22.42 2446 4428 25 Tennant 1804
78 Platinum Pt 195.078 21.45 1768.4 3825 32 Ulloa/Wood 1741
79 Gold Au 196.967 19.32 1064.18 2856 21 Prehistoric ?
80 Mercury Hg 200.59 13.546 -38.83 356.73 26 Prehistoric ?
81 Thallium Tl 204.383 11.85 304 1473 28 Crookes 1861
82 Lead Pb 207.2 11.35 327.46 1749 29 Prehistoric ?
83 Bismuth Bi 208.98 9.747 271.4 1564 19 Geoffroy the Younger 1753
84 Polonium Po 209.00 9.32 254 962 34 Curie 1898
85 Astatine At 210.00 ? 302 ? 21 Corson et al. 1940
86 Radon Rn 222.00 4.45 -71 -61.7 20 Dorn 1900
87 Francium Fr 223.00 ? 27 ? 21 Perey 1939
88 Radium Ra 226.00 5.0? 700 ? 15 Pierre and Marie Curie 1898
89 Actinium Ac 227.00 10.073 1051 3198 11 Debierne/Giesel 1902
90 Thorium Th 232.038 11.72 1750 4788 12 Berzelius 1828
91 Protactinium Pa 231.036 15.373 1572 ? 14 Hahn and Meitner 1917
92 Uranium U 238.029 19.05 1135 4131 15 Peligot 1841
93 Neptunium Np 237.00 20.25 644 154 McMillan and Abelson 1940
94 Plutonium Pu 244.00 19.84 640 3228 164 Seaborg et al. 1940
95 Americium Am 243.00 13.67 1176 2011 134 Seaborg et al. 1944
96 Curium Cm 247.00 13.513 1345 3100 134 Seaborg et al. 1944
97 Berkelium Bk 247.00 14.006 1050 84 Seaborg et al. 1949
33

Atomic
Number
Chemical
Element Name
Symbo
l
Atomic
Weight
Specific
Gravity
Melting
Point, °C
Boiling
Point, °C
No. of
Isotope
s
Discoverer Year
By JGC Annamalai
98 Californium Cf 251.00 900 124 Seaborg et al. 1950
99 Einsteinium Es 252.00 860 124 Ghiorso et al. 1952
100 Fermium Fm 257.00 1527 104 Ghiorso et al. 1953
101 Mendelevium Md 258.00 827 34 Ghiorso et al. 1955
102 Nobelium No 259.00 827 74 Ghiorso et al. 1958
103 Lawrencium Lr 262.00 1627 204 Ghiorso et al. 1961
104 Rutherfordium Rf 263.00 Ghiorso et al. 1969
105 Dubnium Db 268.00 Ghiorso et al. 1970
106 Seaborgium Sg 271.00 Ghiorso et al. 1974
107 Bohrium Bh 270.00 Armbruster & Mnzenberg 1981
108 Hassium Hs 270.00 Armbruster and Mnzenberg 1983
109 Meitnerium Mt 278.00 GSI,Darmstadt,Germany 1982
110 Darmstadtium Ds 281.00 S. Hofmann et al. 1994
111 Roentgenium10 Rg 281.00 Hofmann et al. 1994
112 Copernicium Cn 285.00 2004
113 Nihonium Nh 286.00 1999
114 Flerovium Fl 289.00 2003
115 Moscovium Mc 289.00 2000
116 Livermorium Lv 293.00 2009
117 Tennessine Ts 294.00 2002
118 Oganesson Og 294.00 ?
Elements or their Group: how they were discovered.
Transuration Elements : Neptunium, Plutonium, Americium, Curiem, Berklium, Californium, Einsteinium, Fermium, Mendelevium,
Kurchatovium, Nielsbohrium
Elements Discovered by Chemical Analysis : Cobalt, Nickel, Manganese, Barium, Molybdenum, Tungsten, Tellurium, Strontium,
Zirconium, Uranium, Titanium, Chromium, Beryllium, Niobium, Tantalum
Platinum Metals : Planinum, Palladium, Rhodium, Osmium, Iridium, Ruthenium
Halogens : Fluorine, Chlorine, Iodine, Bromine, Boron, Cadmium, Lithium, Selenium, Silicon, Aluminum, Thorium, Vanadium
Elements Discovered by Electrochemical Method : Sodium, Potassium, Magnesium, Calcium
Elements Discovered by the Spectroscopic Method : Cesium, Rubidium, Thallium, Indium
Rare Earths : Lanthanum, Didymium, Didymium, Termium, Erbium, Ytterbium, Scandium, Holmium, Thulium, Didymium,
Samarium, Neodymium, Praseodymium, Gadolinium, Dysprosium, Ytterbium, Lutetium
Helium and other Inert Gases : Helium, Argon, Krypton, Neon, Xenon,
Elements Predicted from the Periodic system / table : Gallium, Candium, Germanium
Last to be Discovered : Halfnium, Rhenium
Radioactive Elements : Polonium, Radium, Actinium, Radon, Protactinium, Francium
Synthesized Elements : Technetium, Promethium Astatine, Francium
Elements of Air and Water : Hydrogen, Nitrogen, Oxygen
1. Isotopes are different forms of the same element having the same atomic number but different atomic weights.
2. Mass number of the longest-lived isotope that is known.
Elements known in Antiquity : Ancient (pre-historical) : Carbon, Gold, Silver, Copper, Iron, Lead, Tin, Mercury
Elements known in the middle Ages : Phosphorus, Arsenic, Antimony, Bismuth, Zinc
34

Ato.No Element Symbol Ato.Wt. Ato.No Element Symbol Ato.Wt. Ato.No Element Symbol Ato.Wt.
1 Hydrogen H2
1.00784 to
1.00811
41 Niobium Nb 92.91 81 Thallium Tl
2 Helium He 4.00 42 Molybdenum Mo 95.95 82 Lead Pb 207.20
3 Lithium Li
6.938 to
6.997
43 Technetium Tc 97.00 83 Bismuth Bi 208.98
4 Beryllium Be 9.01 44 Ruthenium Ru 101.07 84 Polonium Po 209.00 a
5 Boron B
10.806 to
10.821
45 Rhodium Rh 102.91 85 Astatine At 210.00 a
6 Carbon C
12.0096 to
12.0116
46 Palladium Pd 106.42 86 Radon Rn 222.00 a
7 Nitrogen N
14.00643 to
14.00728
47 Silver Ag 107.87 87 Francium Fr 223.00 a
8 Oxygen O2
15.99903 to
15.99977
48 Cadmium Cd 112.41 88 Radium Ra 226.00 a
9 Fluorine F2 19.00 49 Indium In 114.82 89 Actinium Ac 227.00 a
10 Neon Ne 20.18 50 Tin Sn 118.71 90 Thorium Th 232.04
11 Sodium Na 22.99 51 Antimony Sb 121.76 91 Protactinium Pa 231.04
12 Magnesium Mg
24.304 to
24.307
52 Tellurium Te 127.60 92 Uranium U 238.03
13 Aluminum Al 26.98 53 Iodine I 126.90 93 Neptunium Np 237.00 a
14 Silicon Si
28.084 to
28.086
54 Xenon Xe 131.29 94 Plutonium Pu 244.00 a
15 Phosphorus P 30.97 55 Cesium Cs 132.91 95 Americium Am 243.00 a
16 Sulfur S
32.059 to
32.076
56 Barium Ba 137.33 96 Curium Cm 247.00 a
17 Chlorine Cl2
35.446 to
35.457
57 Lanthanum La 138.91 97 Berkelium Bk 247.00 a
18 Argon Ar 39.95 58 Cerium Ce 140.12 98 Californium Cf 251.00 a
19 Potassium K 39.10 59 Praseodymium Pr 140.91 99 Einsteinium Es 252.00 a
20 Calcium Ca 40.08 60 Neodymium Nd 144.24 100 Fermium Fm 257.00 a
21 Scandium Sc 44.96 61 Promethium Pm 145 a 101 Mendelevium Md 258.00 a
22 Titanium Ti 47.87 62 Samarium Sm 150.36 102 Nobelium No 259.00 a
23 Vanadium V 50.94 63 Europium Eu 151.96 103 Lawrencium Lr 262.00 a
24 Chromium Cr 52.00 64 Gadolinium Gd 157.25 104 Rutherfordium Rf 263.00 a
25 Manganese Mn 54.94 65 Terbium Tb 158.93 105 Dubnium Db 268.00 a
26 Iron Fe 55.85 66 Dysprosium Dy 162.50 106 Seaborgium Sg 271.00 a
27 Cobalt Co 58.93 67 Holmium Ho 164.93 107 Bohrium Bh 270.00 a
28 Nickel Ni 58.69 68 Erbium Er 167.26 108 Hassium Hs 270.00 a
29 Copper Cu 63.55 69 Thulium Tm 168.93 109 Meitnerium Mt 278.00 a
30 Zinc Zn 65.38 70 Ytterbium Yb 173.05 110 Darmstadtium Ds 281.00 a
31 Gallium Ga 69.72 71 Lutetium Lu 174.97 111 Roentgenium Rg 281.00 a
32 Germanium Ge 72.63 72 Hafnium Hf 178.49 112 Copernicium Cn 285.00 a
33 Arsenic As 74.92 73 Tantalum Ta 180.95 113 Ununtrium 113 286.00 a
34 Selenium Se 78.97 74 Tungsten W 183.84 114 Flerovium Fl 289.00 a
35 Bromine Br
79.901 to
79.907
75 Rhenium Re 186.21 115 Ununpentium 115 289.00 a
36 Krypton Kr 83.80 76 Osmium Os 190.23 116 Livermorium Lv 293.00 a
37 Rubidium Rb 85.47 77 Iridium Ir 192.22 117 ununseptium 117 294.00 a
38 Strontium Sr 87.62 78 Platinum Pt 195.08 118 ununoctium 118 294.00 a
39 Yttrium Y 88.91 79 Gold Au 196.97
40 Zirconium Zr 91.22 80 Mercury Hg 200.59 "a" , Atm.wt., Isotope (Longest Half-Life)
Chapter-B5b Atomic Table
204.382 to
204.385
Effect of Alloying Elements, in Iron & Steel By JGC Annamalai
(Extra-Light
Elements,
for
XRF)
(Light
Elements,
XRF)
35

Chapter-B6
(a). Top 10 Strongest Metals/Alloys in the World
1 Carbon Steel
 Carbon Steel has a Yield Strength of 260 Mega Pascals
 Tensile Strength of 580 Moa
 Around 6 on the Mohs scale
 Is highly impact resistant
 Steel can be up to 1000 times stronger than iron
2 Steel-iron-nickel Alloy
 It has a yield strength of 1,420 Mpa
 Tensile strength of 1,460 Mpa
 Iron and nickel are the most abundant metals in metallic meteorites and in the dense metal cores
of planets such as Earth.
3 Stainless Steel
 Yield strength as much as 1,560 Mpa
 Tensile strength up to 1,600 Mpa
 Highly impact resistant
 Between 5.5 to 6.3 on the Mohs scale
4 Tungsten
 Tensile strength at 1,725 Mpa
 Yield strength at 750 Mpa
 Low impact resistance
 Rates 7.5 on the Mohs scale of hardness
5 Tungsten Carbide
6 Titanium
7 Titanium Aluminide
8 Inconel
9 Chromium
10 Magnesium Alloys
Alloys-Strongest, Toughest, Withstand high low Temperatures, Corrosion resistant
Note: The material strength can be changed by chemical composition, rolling/forging, heat treatment and other
strengthening methods. So, pin pointing specific material is difficult. Maraging (Martensitic Aged) steels are said to
have very high strength.
By JGC Annamalai
36

Chapter-B6 Alloys-Strongest, Toughest, Withstand high low Temperatures, Corrosion resistant
By JGC Annamalai
(b). Top 10 Toughest (High Impact Value) Metals / Alloys, for Low / Cryogenic Temperature
37

Chapter-B6 Alloys-Strongest, Toughest, Withstand high low Temperatures, Corrosion resistant
By JGC Annamalai
(c). Top 10 High Temperature Metals / Alloys
Detailed development and analysis, are furnished in Chapter B.7(Superalloys)
(d). Top 10 High Corrosion Resistance Metals / Alloys
38

Alloy-Effect of Alloying Elements in Iron and Steel.pdf

Alloy-Effect of Alloying Elements in Iron and Steel.pdf

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