materials type

1. 1
Metals

2. Major Topics
 History
 Classification of Metals
 Iron
 Steel
 Steel pipe, Tubing, and Wire
 Steel Fasteners
 Rivets
 Structural Bolts
 Welding
 Steel Floor & Roof Framing

3. Major Topics con’t
 Aluminum
 Lead
 Zinc
 Copper and Alloys
 Nickel, Chromium, Cadmium &
Titanium
 Clad Metals

4. History of Metal
 Used as early as 8000 B.C.
 Early civilizations mainly used
metal for weapons, tools, and body
armor
 Metal has been used for
construction material ranging from
simple fasteners to main structural
members

5. Classification of Metals
 2 main classifications
 Ferrous- metals containing a large
percentage of iron (Fe)
 Cast iron
 Wrought iron
 Steel
 Non-Ferrous- metals which do NOT
contain iron
 Aluminum
 Lead
 Copper
 Brass
 Bronze

6. Alloys
 Alloy – a substance composed of
two or more metals

7.  Blanking- in sheet metalwork, the cutting out of a piece of
metal (using a press)
 Braking- a mechanical bending operation usually performed
on sheets and plates
 Casting- an article formed by solidification of molten metal in
a mold
 Cold drawing- drawing metal through a die without the
application of heat
 Cold-rolled- metal rolled at room temperature, below the
softening point, usually harder, smoother, and more
accurately dimensioned that hot-rolled material.
 Drawing- forcing metal to flow into a desired shape without
melting by pulling it through dies
 Embossing- creating a raised surface (design) on metal by die
pressure or by stamping or hammering on the reverse surface
 Extrusion – forcing a molten metal through a die by pressure
 Forging- heating and hammering or pressing metal into a
desired shape

8. Iron
 One of the most abundant metals
on earth
 Commercial iron is composed of
carbon, manganese, silicon,
phosphorus, and sulfur

9. Materials Used to Make Iron
 Iron ore
 Coke- fuel used to melt iron; derived
from coal
 Limestone- used as a flux
 Flux – a material added to react
chemically with impurities and remove
them from molten metal
 Pig Iron- initial molded product from a
blast-furnace; weak & brittle, but very
hard

10. Types of Iron
 Cast iron (and gray cast iron)- brittle metals with high
compressive strength and capacity to absorb vibration.
Lack ductility and therefore should not be hammered or
beaten. Relatively corrosion resistant. Contains 2-4 %
carbon
 Used for gratings, stair components, manhole
covers, some piping
 Wrought iron- soft, corrosion and fatigue resistant, and
easily machined. Contains < 1 % carbon
 Used for railings, grilles, fences, screens, and
various ornamental work

11. Steel
 A malleable alloy of iron and carbon with
substantial quantities of manganese
 3 main methods for making steel
 Open-hearth process
 Oxygen process
 Electric furnace process

12. Mill Output
 Ingot- molded square or rectangular
blocks of cast metal
 Ingots are further squeezed between
rollers to produce:
 Bloom- a rectangular solid of steel
formed from an ingot as an intermediate
step in creating rolled steel structural
shapes (over 36” square)
 Billet- a large cylinder or rectangular solid
of metal (smaller then 36” square)
 Slab – if the width is 2x the thickness or
more

13. Standard Mill Products
 Angle- a section of metal rolled, drawn, or extruded through L-
Shaped rolls or dies
 Bar- round, square, rectangular, hexagonal, or solid stock of
drawn, rolled, or extruded metal. A rod.
 Channel – a rolled, drawn, or extruded metal section having a U
shape.
 Flat- a rectangular bar whose width is greater than its thickness
 Pipe, round- a hollow, round section of metal, the size of which is
determined by the nominal inside diameter in inches
 Pipe, square- a hollow, square section of metal, the size is
determined by the nominal outside diameter in inches
 Plate- a flat piece of metal; various metals are defined as plate by
the following thickness criteria: Aluminum==1/4” or more;
Copper==.188” or more; Steel (including stainless)== 3/16” or
more

14. Designations of Rolled Steel Shapes
 W – wide flange
 S -- beams
 C –channels
 L – angles (may be equal or unequal legs)
 WT or MT – structural tees

15. Example of Designation
 W 36 x 300
 W === a wide flange beam
 36 === indicates a beam 36” deep
 300 === weight in lbs/ linear feet

16. Samples of
Steel Shapes
Channel
Square & Rectangular
Tubing
Angle
Tee
S-Beam
Wide Flange

17. Steel Wire
 6 million tons of wire produced in the U.S. annually
 Shapes are not only round, but may also include:
square, rectangular, and polygonal
 Wire is used as the starting material to form nails,
bolts, screws, rivets, and welding electrodes
 Temper- wires hardness, stiffness, and strength is
affected by the amount of carbon and alloying agents,
number of passes through dies, and the final heat
treatment
 Wire may be produced with different finishes and
coated, painted, or plated depending on its intended
use

18. Classification of Steel
 Four main specifications
 Method of manufacture
 Heat treatment
 Chemical composition
 Reference to a recognized
standard

19. Stainless Steel
 To be considered stainless a steel
must contain 11.5 % chromium
 There are basic series of stainless
steel: 200, 300, 400, & 500 series
 Available in many finishes ranging
from matte to highly reflective
(mirror)

20. Structural Steel
 Consists of hot-rolled steel section, shapes, and
plates not less than 1/8” thick
 The most commonly used strength grade is
36,000 psi yield strength (ASTM 36)
 For heavily loaded members such as columns,
girders, or trusses, a high strength, low alloy steel
with a yield strength of 50,000 psi

21. Steel Construction
 3 basic types:
 Wall bearing
 Skeleton framing
 Long-span
 Large industrial buildings, auditoriums, sports
arenas
 Often use steel trusses, steel arches, or rigid bents
in this type of construction (see figures 5-17, 5-18,
and 5-19 on page 127)

22. Steel Fasteners
 3 main types of fasteners:
 Rivets
 Bolts
 Unfinished (common, machine)
 High-strength structural bolts- resist vibration
(ASTM 325 or A490 are stamped on bolt head)
 Welds
 In some application (based on code
requirements) more than one method may be
used

23. Welding
 A process of joining metals by applying heat
and pressure, with or without filler material,
to produce an actual union through fusion.
 There are several methods of welding used
in specific situations (shielded metal arc is
the most common in steel work).
 Welding symbols and basic joints are
standardized by AWS (American Welding
Society) – see figure 5-28 on page 132

24. Steel Floor and Roof Framing
 Considerations for systems used:
 Span
 Load to be applied
 Depth
 Weight
 Fire resistance (code)
 Sound transmission
 Heating/Cooling system
 Appearance
 Cost/Time

25. Open Web Steel Joists
 Widely used because of the long spans
 See figure 5-29 on page 133 for types
 Ends of open web joists (hung from the top
chord) are extended a minimum of 4 “ in
masonry/concrete, and a minimum of 21/2 “
over steel supports.
 Corrugated or ribbed steel decking many
times used in combination with the joists.

26. Aluminum
 Bauxite, the major source of aluminum, is still
very abundant in the earth (Jamaica)
 Highly resistant to weather and corrosive
environments
 Aluminum can be economically extruded to many
shapes (mouldings, edgings, window mullions)
 It is very malleable, quite ductile, non-corrosive,
and strong in proportion to its weight.

27. Lead
 Important physical properties include:
resistance to corrosion, its plasticity, and its
malleability
 Used for waterproofing, sound and vibration
isolation, and radiation shield.
 Can be combined with a tin alloy to plate iron
or steel (called “terneplate”)
 Use extreme care where and how lead is
used because lead vapors or dust are toxic if
ingested.

28. Zinc
 Is brittle and low in strength
 Major use is in galvanizing (dipping hot
iron or steel in molten zinc)
 May also be used for roofing, flashing, and
hardware

29. Copper
 Resistant to corrosion, impact, and
fatigue; very ductile
 Primary use is electrical wiring,
roofing, flashing, and piping
 The oxidization of copper produces
what is called a green “patina”

30. Bronze
 Originally a copper-tin alloy, but now
aluminum or silicon added to copper
 Now may be “phosphor bronze”, “aluminum
bronze” or “silicon bronze”
 Widely used for casting delicate mold
impressions (Cathedral doors)

31. Brass
 Copper with zinc to form an alloy
 Used for doors, windows, railings,
trim, grilles and for finish hardware

32. Nickel, Chromium, and Monel
 Chromium and nickel are used primarily as
alloying elements, however, both can take a
bright polish and do not tarnish in air,
making them ideal for use in plating.
 Monel, a nickel-copper alloy, is mostly used
to make fasteners and anchors, and has
excellent corrosion resistance.

33. Clad Metals
 Combines the best qualities of 2 or
more different materials
 The intent is to create a
metallurgical bond between layers
of materials

34. Galvanic Action
Corrosion occurs between dissimilar metals
when sufficient moisture is present to carry
an electric current. The galvanic series, a
list of metals arranged from “least noble
(anode)”, most reactive, to “most noble”
(cathode), is an indicator of corrosion
susceptibility. The farther apart the metals
are on the list, the greater the deterioration
of the least noble one.