Cast iron is an alloy of iron that contains 2-4% carbon, along with other elements like silicon and manganese. It is classified into gray, white, ductile, and malleable cast iron based on its composition and microstructure. Cast iron has high compressive strength but low tensile strength. It is brittle and not suitable for applications requiring flexibility. Historically, cast iron was widely used in construction for elements like bridges, columns and architectural details from the 18th century onward due to its low cost. However, it is prone to corrosion and cracking over time. Modern applications of cast iron include machine parts and components that require good castability and heat resistance.

1. CAST IRON
1
SUBMITTED BY:
AAESHA QAMAR, FATIMA AJAZ, HARPAL SINGH,
MARIA SHAMSI, PRIYANSHU MEHTA, TAUSEEF RAHI, SHIV KUMAR

2. IRON
2
INTRODUCTION:
Out of all the metals, the iron is the most popular metal and it has been in
the construction activity since pre historic times.
Iron is a chemical element with the symbol Fe and atomic number 26
It is available in abundance and it is estimated that it constitutes about
4.60% of the crust of the earth.
In latin, the iron is known as ferrum and its chemical designation is Fe.
The metals are grouped in the two categories.
1.FERROUS METALS: The ferrous metals contains iron as their main
constituent. There are three important ferrous metals, namely, cast iron,
wrought iron and steel.
2.NON FERROUS METALS: non ferrous metals do not contain iron as
their main constituent. Eg. Aluminium, copper etc.

3. 3
Iron OreIron Ore
Blast FurnaceBlast Furnace
Pig IronPig Iron
Smelted, Hammered, Re-
heated, Rolled
Smelted, Hammered, Re-
heated, Rolled
Smelted,Alloyed, RolledSmelted,Alloyed, Rolled
Wrought IronWrought Iron Cast IronCast Iron Mild Iron(Steel)Mild Iron(Steel)
Re- melted,
Poured into sand
molds
Re- melted,
Poured into sand
molds

4. 4
COMPARISON BETWEEN WROUGHT IRON ,CAST IRON& STEEL
Wrought iron Cast Iron Steel
Compositio
n
Purest Contains up
to 0.25% C
Crude form
containing 2-4% C
Midway
Melting
point
1500 degree Celsius 1200 degree
Celsius
1300-1400 degree
Celsius
Hardness Cannot be hardened
or tempered
Hard, hardened by
heating & sudden
cooling
Can be hardened
& tempered
Strength compressive strength
is 2.0 tonnes/sq cm
ultimate tensile
strength 3.15
tonnes/sq cm
Comp. strength
6.3-7.1 tonnes/sq
cm
Ultimate tensile
strength 1.26 to
1.57tonnes/sq cm.
Comp strength
4.75 -25.2 tonnes/
sq cm
Ultimate tensile
strength is 5.51 to
11.02 t /sq m

5. 5
Wrought iron Cast Iron Steel
Rusting Rusts more than
Cast Iron
Does not rust
easily
Rusts easily
Malleability&D
uctility
Tough, malleable,
ductile &
moderately elastic
Brittle & cannot
be welded or
rolled into
sheets
Tough, malleable
& Ductile
Reaction to
sudden shock
Cannot stand heavy
shocks
Does not absorb
shocks
Absorbs shocks
Welding Easily welded Brittle and
cannot be
welded or
rolled into
sheets
Rapidly welded

6. 6
Wrought iron Cast Iron Steel
Uses Costlier than
mild steel so
being replaced
by the latter.
Withstand
shocks without
permanent
injury so used
in chains,
crane hooks
and railway
couplings
For parts that
rust easily like
water pipes,
sewers,
drain pipes
etc.
Making such
parts of
machines as
are not likely to
be subjects to
shocks or
tension
Lamp posts,
columns and
Used as
reinforcement
in R.B. & R.C.C.
Used in making
St. members,
bolts, rivets
and sheets
(plain and
corrugated)
Making cutlery,
files &
machine tools

7. 7
CAST IRON
Cast iron used in Door
Cast iron used in Bolt-nuts
Cast iron is the name given to those ferrous metals
containing more than1.7 % carbon.
It is similar in composition to crude pig iron as produced
by the blast furnace.
Its structure is crystalline and relatively brittle and weak in
tension.
Composition of Cast Iron:
Carbon - 2.5 to 3.7%
Silicon - 1.0 to 3.0%
Manganese - 0.5 to 1.0%
Phophorus - 0.1 to 0.9%
Sulphur - 0.07 to 0.10%
Introduction:

8. 8
BRIEF HISTORY
Cast iron has its earliest origins in China between 700 and 800 BC and in
Europe it was first known in the 14th century.
Until this period ancient furnaces could not reach sufficiently high
temperatures.
The use of this newly discovered form of iron varied from simple tools to a
complex chain suspension bridge erected approximately 56 A.D.
Cast iron was not produced in mass quantity until fourteenth century A.D.
In 1325 A.D. water driven bellows were introduced which allowed for a greater
draft to be fed to the pit, thus increasing temperatures.
The next significant development in cast iron was the first use of coke in 1730
by an English founder named Darby.
Coke could be used more efficiently than coal, thus lowering the cost and time
necessary to yield a final product.

9. 9
In 1885 Turner added ferrosilicon
to white iron to produce stronger
gray iron castings.
In the later 20th century the major
use of cast irons consisted of pipes,
thermal containment units, and
certain machine or building entities
which were necessary to absorb
continuous vibrations.

10. MANUFACTURING PROCESS
10
cast iron is manufactured by remelting pig iron with
coke and limestone.
this is done in a furnace known as cupola furnace.
The raw materials are fed from the top
The cupola furnace is worked intermittently and it
is open at the top.
After raw material is placed, furnace is fired and
blast of air is forced.
The blast of air is cold as the impurities in pig-iron
are removed by the oxidation.
The impurities of pig iron is removed and pure iron
is taken in the molten stage from the bottom of
furnace. CUPOLA FURNACE
The slag is also removed from the top of the cast iron. At regular intervals.
Molten cast iron are led into moulds of required shapes to form what we known as cast
iron.

11. PROPERTIES OF CAST IRON
11
It is strong in compression but weak in tension.
The tensile and compressive strengh of cast iron of average quality is
150N/mm² and 600N/mm² resp.
It does not rust easily.
If placed in salt water, it becomes soft.
 low melting pont
Good fluidity
It is hard but it is brittle also.
It is not ductile hence it cannot be adopted to absorb shocks and
impacts.
Its melting temperature is about 1250 C.⁰
It shrinks on cooling.

12. EFFECT OF COOLING RATE
12
Slow cooling favours the formation of graphite and low hardness.
Rapid cooling promotes carbides with high hardness.
Thick sections cools slowly, while thin sections cools down quickly.
Sand moulds cools slowly but metal chills can be used to increase cooling
rate and promotes white iron.

13. 13
Cast iron is used in a wide variety of structural and decorative applications,
because it is relatively inexpensive,
durable &
easily cast into a variety of shapes.
AppLICATIONs
Construction of machines and structures
(HighTensile Strength)
As Columns,balusters & Arches
(High Compressive Strength)
 Machine and car parts like
cylinder heads,
blocks,
gearbox cases,
cookware,
pipes, etc.
(Good Castability)
machines internal
detailing
ColumnsArches in bridgeSwing Machine

14. 14
Stoves and firebacks,
Vehicles engine
(High thermal conductivity
and specific heat capacity)
Car Engine
Used for Decorative purposes:
Stoves
Cookware
(Good fluidity,elasticity)
Design made on
column
gate design Decorative pattern

15. 15
DIsADvANTAGEs:
Cast Iron Weight
Cast iron is very heavy, and consequently is
mush harder to install than regular
PVC/ABS sewer pipe.
Brittleness
It is quite brittle and if accidentally knocked
will easily break.
Brittleness in cast Iron
Its strength and stiffness deteriorate when
subjected to high heat, such as in a fire.
weak in tension and bending, so can’t be
used as beams
Can’t overcome from Environmental causes
Or can’t absorb sudden shocks
Resistance towards heat

16. EARLy sTRuCTuRAL usEs OF IRON IN buILDINGs
16
Cast iron is used for structural element between late 1830’s to1910
Because cast iron is comparatively brittle, it is not suitable for purposes
where a sharp edge or flexibility is required. It is strong under compression, but
not under tension
Architecturally Cast-Iron used in two ways:
1.Structural use
2.Architectural use
1.Structural use
1.The best way of using cast iron for bridge
construction was by using arches, so that
all the material is in compression.
Bridge

17. EARLy sTRuCTuRAL usEs OF IRON IN buILDINGs
17
Cast iron is used for structural element between late 1830’s to1910
Architecturally Cast-Iron used in two ways:
1.Structural use
2.Architectural use
Cast iron was the metal of choice throughout the second 19th
century.
It was a fire resistance material
Large facades could be produced at less cost.
Iron buildings could be erected with speed and efficiency.

18. It was a prominent style in the Industrial Revolution era when cast iron was
relatively cheap and modern steel had not yet been developed.
18
Structural use
Cast iron has been used for centuries, and was used in
architecture
•It was in 18th century Britain that new production methods first
allowed cast iron to be produced cheaply enough and in large
enough quantities to regularly be used in large building projects.
•
•One of the first important projects was The Iron
Bridge in Shropshire, a precedent setting structure made almost
entirely of cast iron.
• However, it was grossly over-designed, and the makers
(principally Abraham Darby) suffered financially as a result.
•The quality of the iron used in the bridge is not high, and nearly 80
brittle cracks are visible in the present structure.
•Later designers and engineers, such as Thomas
Telford improved both the design and quality of the material in his
bridges (for example, at Buildwas upstream of Coalbrookdale) and
aqueducts (such as the world-famous Pontcysyllte Aqueduct in
North Wales.)
Close up view of cast-iron detailing at the Ca'
D'Oro Building in Glasgow, Scotland, erected
in 1872

19. THE IRON BRIDGE
• The Iron Bridge crosses the River
Severn in Shropshire, England.
• It was the first arch bridge in the world to be made
of cast iron, a material which was previously too
expensive to use for large structures.
• Carries pedestrian traffic
Crack and repairs in bridge
Cracked supports

20. CONSTRUCTION
• Being the first of its sort, the construction had no
precedent; the method chosen to create the structure
was therefore based on carpentry.
• Each member of the frame was cast separately, and
fastenings followed those used in woodworking, such as
the mortise and tenon and blind dovetailjoints, adapted
as necessary to the different properties of cast iron.
• Bolts were used to fasten the half-ribs together at the
crown of the arch.
• Very large parts were needed to create a structure to
span 100 feet rising to 60 feet above the river.
• The largest parts were the half-ribs, each about 70 ft
long and weighing 5.25 tons.
• The bridge comprises more than 800 castings of 12 basic
types.
• The bridge was raised in the summer of 1779, and it was
opened on New Year's Day 1781.

21. 21
Columns Roof Trusses Long span roof
2.Cast iron columns had the advantage of being slender, compared with masonry
columns capable of supporting similar weight.
Buildings
2.Architectural use
As an Architectural metal, it gives architectural design& building technology,
while providing a richness in ornamentation, much cheaper than stones.

22. 22
.
Its use gradually spread from architectural elements like shutter and door frames to facades
composed of closely spaced iron columns and spandrel panels to interior columns.

23. 23
FAILURE
:
Oxidation or rusting occurs rapidly when cast iron is exposed to
moisture or air.
The casting process also left flaws in the cast iron (such as blow holes,
bubbles, imperfectly joined seams) that serve to concentrate stress in
unpredictable ways.
Common problems encountered with cast iron construction include
Badly rusted or missing elements.
Impact damage
Structural failures
Broken joints
Damage to connections
Loss of anchorage in masonry
Steel was becoming available nationally, and was more versatile and
cost competative.

24. Compositions of Cast iron
24
The cast iron contains about 2-4% of carbon. In addition it contains the various impurities
such as manganese, phosphorous, silicon and sulphur.
1. MANGANESE: (Below 0.75%)
 It makes cast iron hard and brittle.
 Its amount should therefore be kept
below 0.75% or so.
2. SULPHUR: (Below 0.10%)
 It makes cast iron brittle and hard.
 Does not allow smooth cooling in
sand moulds.
 Its presence causes rapid solidification
of cast iron and it ultimately results in
blow holes and sand holes.
 Sulphur content should be kept below
0.10%
3. SILICON: (Below 2.5%)
 It combines with part of iron and forms a
solid solution.
Removes combined carbon from graphite
form.
If its amount is less than 2.5%, it decreases
shrinkage and ensures softer and better
casting.
2.PHOSPHORUS: (0.3-1%)
It increases fluidity and also makes it
brittle.
When its amount is more than 0.3% the
resulting cast iron is lacking in toughness and
workability.
Its % is some times kept as about 1-1.5 to
get very thin casting.

25. 25
Comparative table
Name
Nominal
compositi
on [% by
weight]
Form and
condition
Yeild
Strength
Tensile
strength
Ductility Hardness Uses
Grey cast
iron
C :3.4,
Si:1.8,
Mn: 0.5
Cast Low High Low Average
Engine cylin
der blocks,
flywheels, ge
ars machine-
tool bases
White cast
iron
C :3.4,
Si :0.7,
Mn: 0.6
Cast (as cast) Lowest Low Lowest Highest
Bearing surfa
ces
Malleable
iron
C :2.5,
Si :1.0,
Mn :0.55
Cast
(annealed)
High High High Lowest
Axle bearing
s, track
whee,Colum
n, arches
Ductile Iron
C :3.4,
P :0.1,
Mn:0.4, Ni:1.
0, Mg :0.06
Cast Highest Highest Highest Low
Gears, camsh
afts,
crankshafts

26. ClassifiCations of Cast iron
26
1.WHITE CAST IRON
2.GRAY CAST IRON
3.DUCTILE (NODULAR) CAST IRON
4.MALLEABLE CAST IRON

27. 1. WHite Cast iron
27
 These are iron-carbon alloys having more than 2.11%
carbon.
 All the carbon is present in the combined cementite
form, which makes the fracture of these alloys to have
dull and white colour, and that is the reason of their
name as white irons. Microstructure of White Cast Iron
Composition:
C=2.5%,Mn=0.4%,
Cr=17%,Si=1.3%,
Ni+Cu=1.5%,P=0.15%,
S=0.15%,Mo=0.5%

28. properties of WHite Cast iron
28
Hard and wear resistant
The hardness and brittleness increases as the carbon content increases.
Hardness Brinell 375 to 600.
Tensile strength 20000 to 70000 psi.
Compressive strength 200000 to 250000.
limitations
Because of extreme brittleness and lack of machinability, white irons find
limited engineering applications.

29. 2929
appliCations
Used to Make Malleable Iron
Malleabilize
To Increase Ductility
White Cast Iron Malleable Cast Iron→
Liners For Cement Mixers,
Ball Mills,
Certain Types Of Drawing Dies
Extrusion Nozzles
(abrasion resistance) Liners For Cement Mixers
Ball Mills
Nozzles
 In furnitures
(Wear resistant)
Toughness
Decorated furnitures

30. 2. Grey Cast iron
30
Iron-carbon alloys containing flakes of
graphite embedded in steel matrix, which
show a gray-blackish coloured fracture due to
graphite’—the free foam of carbon, are called
gray cast irons.
The strength of gray iron depends on the
strength of steel matrix and the size and character
of graphite flakes in it.
Microstructure of Gray Cast Iron
A typical feature of gray iron is that graphite is in the form of flakes in
microstructure.
COMPOSITION:
Total carbon : 2.4—3.8%
Silicon : 1.2—3.5%
Manganese : 0.5—1.0%
Sulphur : 0.06—0.12%
Phosphorus : 0.1—0.9%

31. properties of Grey Cast iron
31
1. Low cost of production
2.Low melting point: (1150°—1250°C) of cast irons, several hundred degrees less than
steel.
3. Good Castability: Cast irons have excellent fluidity and take good mould-impressions
easily. Graphite having low density is voluminous. Its large volume compensates for the
shrinkage. Gray iron, thus, does not need shrinkage allowance at all to take almost exact
casting impressions.
4. Good machinability of gray cast iron is due to easy and discontinuous chip
formation due to brittle graphite flakes.
Graphite serves as a solid lubricant decreasing coefficient of friction.
It smears the cutting tool allowing free sliding of chips increasing thus, tool life too.
(White cast irons, due to high hardness, are unmachinable).

32. 32
5. Good wear resistance of gray iron is due to graphite acting as solid lubricant layer,
avoiding thereby metal to metal direct contact. On other hand, white cast irons are wear
resistant due to’ their high hardness.
6. High damping capacity is due to the graphite flakes, which breaks the continuity of
the metallic matrix, and thus, vibrations are not allowed to transfer from one side of
flake to other, i.e., graphitic cracks quickly dampen the vibrations and resonance
oscillations. Gray iron suits thus the machine beds as compared to steels.
7. High compressive strength of gray iron- almost 3 to 5 times of its tensile strength
(110-350 N/mm2), and almost equal to that of steels makes it suitable for applications,
where components are subjected to compression such as machine beds, etc.
8. High thermal conductivity, and have ability to withstand thermal shocks.
9.Good resistance to atmospheric corrosion due to high silicon and perhaps other
factors, than mild steels.
10. Notch-insensitive: Large number of flakes in gray iron acts as notches in spite of
these notches, if gray iron has the required strength, then additional notch or notches
shall have minor, or no effect, i.e., gray iron is notch-insensitive; whereas in steels. A
notch has quite a damaging effect as it acts as stress-raiser to make the steel even
brittle.

33. 33
appliCations
Internal Combusion Engine
Pump Housings
Valve Bodies
Electrical Boxes
Decorative Castings
Cast iron cookware
Disc brake
(High thermal conductivity
and specific heat capacity)
(Low Tensile Strength)
Internal combustion engine
Pump Housings
disc brake on a carCast iron cookware
(Good Castability)
Decorative pattern

34. 3. Malleable cast iron
34
Malleable iron is cast as White iron, the structure being a metastable
carbide in a pearlitic matrix.
Microstructure of Malleable Iron
Components Percentage
Carbon 2.00-2.65
Silicon 0.90-1.40
Manganese 0.25-0.55
Phosphorus Less than 0.18
Sulphur 0.05
Composition of Malleable Iron
Graphite in nodular form
Produced by heat treatment of white cast
iron
Graphite nodules are irregular clusters
Similar properties to ductile iron.

35. properties
35
Similar to ductile iron
Good shock resistance
Good ductility
Good machineability

36. applications
 Malleable iron is better for thinner castings
 Vehicle components
– Power trains, frames, suspensions and wheels
– Steering components, transmission and differential parts,
– connecting rods
 Railway components
 Pipe fittings
(Good Tensile Strength)
(High ductility)
Rail tracks Pipe fittings
(Good Machinability)
Power trains
wheels
Steering components in car

37. 4. Ductile (noDule ) cast iron
37
In ductile irons, the graphite is in the formof spherical nodules rather than
flakes (as in grey iron), thus inhibiting the creation of cracks and providing
the enhanced ductility.
Also known as spheroidal graphite (SG), and nodular graphite iron.
COMPOSITION:
A TYPICAL CHEMICAL ANALYSIS OF THIS
MATERIAL
IRON
CARBON 3.3 TO 3.4%
SILICON= 2.2 TO 2.8%
MANGANESE 0.1 TO 0.5%
MAGNESIUM 0.03 TO 0.05%
PHOSPHORUS 0.005 TO 0.04%
SULPHUR 0.005 TO 0.02%
Microstructure of Ductile Iron

38. properties
38
Strength higher than grey cast iron
Ductility up to 6% as cast or 20% annealed
Low cost
Simple manufacturing process makes
complex shapes
Machineability better than steel

39. 39
applications
 Pipe and pipe fittings
Major industrial applications include
--highway diesel trucks,
--agricultural tractors,
--oil well pumps.
– Crankshafts,
– front wheel spindle supports,
– steering knuckles,
– disc brake callipers
used for water and sewer lines.
Pipes
(High strength)
Machinery products:
Tracters
spindle
(Good Machinability)
oil well pumpsCrankshafts in motor engine
disc brake callipers

40. Market survey
40

41. 41
size ½” ¾” 1” 1 1/4” 1 ½” 2” 2 ½” 3” 4” 6”
weight 15mm 20mm 25mm 32mm 40mm 50mm 65mm 80mm 100m
m
150m
m
Ball
valve
281 436 585 960 1497 2287
Multip
urpose
gas ball
valve
556 796 1182 1670 2565 3809
b.V
with
inbuilt
straine
r
993 1329 1848
Spring
loaded,
uni
directio
nal
391 572 859 1221 1826 2470
Ball
valve
14M
6397 9102 1538
4

42. 42
size ½” ¾” 1” 1
1/4”
1
½”
2” 2 ½” 3” 4” 6”
weight 15m
m
20m
m
25m
m
32m
m
40m
m
50mm 65mm 80mm 100m
m
150m
m
Butterfly
handle
281 436 585
Gas ball
valve
628
Mini ball
valve
395
Non return
valve
364 489 761
Ball valve
(with
flexible
connection)
714
Right angle
mini ball
valve
453
(15 mm Male x 8mm Nozzle)

43. unik
43