Metals
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All metals are classified into:
Ferrous
metals:
Wherein iron is the main
constituent (Cast
iron, wrought iron and
different forms of
steels)
Non-Ferrous metals:
Wherein
iron is not the
main constituent (Copper, Aluminum,
Zinc and lead
etc)
Non ferrous alloys: Alloys
of copper |
a) Ferrous metals
IRON:
Iron is produced in a blast furnace through a chemical reaction by smelting the iron ore.
The iron is then further refined through additional melting and blending processes to create
products that’s listed beow:
1) CAST IRON:
Cast iron is another type of alloy that can
be refined from the initial material. Cast iron is stronger and less
breakable than the initial material, thanks to a process that removes
carbon, and other elements while adding desirable characteristics thanks
to melted scrap metal and steel. Once popular as bridge and building
material, cast iron is also used to create pots and pans that withstand
and distribute high heat evenly.
2) WROUGHT IRON
Wrought iron is a soft, easily worked, fibrous metal. It
usually contains less than 0.1% carbon.
It is superior for most purposes to cast
iron, which is hard and brittle because of its higher carbon
content.
Since mild steel has replaced the wrought
iron, therefore it is no longer produced in large extent.
3) STEEL
Steel is an alloy of iron and carbon. Pure iron’s strength remarkably
increases when alloyed with carbon. The tensile strength increases with
increasing carbon content but the ductility reduces. Structural steel has
a low carbon content.
PLAIN CARBON STEEL can further be classified as:
- Low carbon steel or mild steel: iron with up to 0.30% carbon
alloyed with it. The bulk of construction steel has Grade:
300PLUS®,which has replace the Grade 250 MPa and 350 MPa
- Medium-carbon steel : carbon content is 0.30 to
0.5 % Stronger than the mild steel s but lightly less ductile
- High- carbon steel : carbon content is above 0.5% harder and
stronger than mild steel and medium carbon steel
Steel products are supplied in accordance with AS/NZS 3678 (Structural
steel - hot-rolled plates and floor plates), AS/NZS 1594 (Hot-rolled steel
flat products), AS1548 (Steel plates for pressure equipment) and
AS/NZS1365 (Tolerances for flat-rolled steel products).
These specifications cover such matters as testing, inspection, certification
procedures and dimensional tolerances.
Structural Sections available comprise: Solid Angles; Beams;
Columns; Welded Beams; & Hollow Section
Hot-Rolled Structurals Beams, Universal
Columns, Angles (Equal & Unequal) Hot Rolled Structural Steel
sections are manufactured in accordance with the requirements of
Australian/New Zealand Standard AS/NZS 3679.1 Structural steel –
Hot-rolled bars and sections.
Cold-Formed Structurals
Hollow Sections (Square, Rectangular & Circular)
b) Non-Ferrous metals
Non-ferrous metals are metals that do not
contain iron. There are two groups of metals; ferrous and non-ferrous.
Ferrous metals contain iron, for example carbon steel, stainless steel
(both alloys; mixtures of metals) and wrought iron. Non-ferrous metals
don't contain iron, for example aluminium, brass, copper (which can be
remembered as ABC) and titanium. You can also get non-ferrous metals as
alloys eg, brass is an alloy of copper and zinc.
Nonferrous metals are specified for
structural applications requiring reduced weight, higher strength,
nonmagnetic properties, higher melting points, or resistance to chemical
and atmospheric corrosion. They are also specified for electrical and
electronic applications.
Non - Ferrous
Metals |
Aluminum |
Copper |
Lead |
Zinc |
Brass |
Bronze |
Aluminum
Pure aluminum is a silvery-white metal with many desirable
characteristics. It is light, nontoxic (as the metal), nonmagnetic and
nonsparking. It is easily formed, machined, and
cast. Because of aluminum's mechanical and
physical properties, it is an extremely convenient and widely used
metal.
Uses in
Building:
Door and
window frames
wall
cladding, roofing, awnings etc.
Copper
Copper provides a diverse range of
properties: good thermal and electrical conductivity, corrosion resistance
and ease of forming. Next to silver, copper is the next best electrical
conductor. It is a yellowish red metal that polishes to a bright metallic
luster. It is tough, ductile and malleable.
Copper and its alloys -- the
brasses and bronzes -- are available in rod, plate, strip, sheet, tube
shapes Uses in Building:
Roofing. plumbing (pipes & fittings),
electrical wiring etc
Lead Lead is the most impervious of all common metals
to Xrays and gamma radiation and it resists
attack by many corrosive chemicals, most types of soil, and marine and
industrial environments. Main reasons for using lead often include, ease
of forming, high density, good sound and vibration absorption, and ease of
salvaging from scrap. Uses in Building: Flashing, roofing, damp coursing etc.
Zinc
Zinc is a silvery blue-grey metal .When
unalloyed, its strength and hardness is greater than that of tin or lead,
but appreciably less than that of aluminium or copper. One of the most
useful characteristics of zinc is its resistance to atmospheric corrosion,
and just over half of its use is for the protection of steelwork.
In addition to its metal and alloy forms,
zinc also extends the life of other materials such as steel (by hot
dipping or electro-galvanizing). Zinc is also used to make brass,
bronze. Uses in Building: Roofing, hot dipping, electro-galvanizing,
ZINCALUME® steel) roofing, framing, garage doors, guttering
etc.
c) Non
ferrous alloys
These are metals which do not contain any iron. They are not
magnetic and are usually more resistant to corrosion than ferrous
metals.
Brass
Brass is a metal composed primarily of copper and zinc. Copper is
the main component, and brass is usually classified as a copper alloy.
Brass is stronger and harder than copper, but not as strong or hard as
steel. It is easy to form into various shapes, a good conductor of heat,
and generally resistant to corrosion from salt water. Uses in
Building: plumbing, hose and brass tube fittings
Bronze
It is hard
and brittle, and it was particularly significant in olden days, so much so
that the Bronze Age was named after the metal. Traditional bronze is a
copper alloy with up to 10% tin. The tin in bronze makes it more resistant
to wear than unalloyed copper. Bronze
parts are typically used for bearings, clips, electrical connectors and
sculpture.
Other
types of bronze:
Aluminium
bronze is a
copper-aluminium alloy that may contain iron, nickel, and/or silicon for
greater strength. Aluminium bronze is frequently used for aircraft and
automobile engine parts. Manganese
bronze (a brass
containing manganese. It is often used for ship propellers because it is
strong and resists saltwater corrosion)
I did include a more comprehensive website Engineering Material
as suggested by
"Arthur Kirkby"
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