BT1 - Metals

3rd module of BT1

Alloys

mixture of a base metal and one or more additional elements

Aluminum

for surface hardening

Copper

for atmospheric corrosion

Manganese

small amounts for hardening; larger amounts for wear resistance

Molybdenum

combined with other alloying metals, such as chromium and nickel, increase corrosion resistance and raise tensile strength without reducing ductility.

Nickel

increases tensile strength without reducing ductility; in high concentrations, improves corrosion resistance

Silicon

strengthens low alloy steels and improve oxidation resistance; in larger amounts provides hard, brittle castings resistant to corrosive chemicals.

Sulfur

free machining; especially in mild steels

Titanium

prevents inter-granular corrosion of stainless steels

Hardness and Abrasion Resistance

Tungsten, Vanadium and Cobalt

Steel

A malleable alloy of iron and carbon (combined) produced by melting and refining of pig iron and/or scrap steel

Alloy Steel

a kind of steel made by combining other elements to steel such as nickel, chromium, copper, and manganese.

Nickel Steel

a kind of steel stronger than carbon steel and is used to make structural members for buildings

Carbon Steels

iron that contains low to medium amounts of carbon

Stainless Steel

made from adding chromium or a combination of nickel and chromium

Weathering Steel

forms its own protection against atmospheric corrosion and thus requires no painting

• formulated to produce a dense, stable oxide layer that provides sufficient protection without the need for coating systems

Wrought Iron

produced from pig iron in such a way to remove nearly all the carbon and other impurities

Galvanized Iron

Iron coated with zinc to prevent rust. The process is achieved thru hot-dip galvanizing.

Sheet Piling

sections of sheet material used to provide earth retention and excavation support.

Steel Pipe

Galvanized steel pipes has a thin coating of zinc which protects it from corrosion.

Reinforcing Steel

comes in plain or deformed bars

• has lugs or deformations rolled on the surface to provide anchorage to concrete

Welded Wire Fabric

 reinforcing material (to concrete)

 Consist of parallel, longitudinal wires welded to transverse

Steel Wire

uses in construction includes pins, nails, bolts, cables and fences

Steel Strapping

Made from high tensile flat wire in a number of sizes.

• Used for banding column forms to keep them from bulging under pressure of freshly poured concrete.

Open Web Steel Joists

Lightweight warren-type trusses.

Sheet Steel

black and galvanized, can be used to manufacture corrugated roofing and siding and formed steel decking.

Aluminum

Soft, non-magnetic, ductile and malleable silvery white metal with thermal and electrical conductivity

Aluminum

the most abundant metal in the Earth’s crust, and the third most abundant element therein, after oxygen and silicon

Anodizing

done by dipping the aluminum profiles into acid electrolyte bath chemicals and then passing an electric current

• creates an oxide layer on top of the aluminum for surface corrosion protection and design finishes

Copper

Ductile, malleable and bright reddish-brown color with high thermal and electrical conductivity

Brass

an alloy of cooper and zinc which has muted yellow color, somewhat similar to gold

Lead

It is a soft, malleable poor metal, also considered to be one of the heavy metals.

 has a bluish white color when freshly cut, but tarnishes to a dull grayish color when it is exposed to air and is a shiny chrome silver when melted into a liquid.

 Very easy to work, enabling it to be fitted over uneven surfaces.

 Common uses: roofing, flashing, and spandrel wall panels.

Tungsten Carbide

chemical compound containing tungsten and carbon, similar to titanium carbide

Soldering

a process in which two or more metal items are joined together by melting and flowing a filler metal into the joint, the filler metal having a relatively low melting point. (below 840 degrees F)

• by use of a lower melting-temperature filler metal

• distinguished from welding by the base metals not being melted during the joining process

Annealing

In the case of copper, steel, and brass, this process is performed by substantially heating the material (until glowing) for a while and allowing it to cool slowly. The metal is softened and prepared for further work such as shaping, stamping, or forming.

Brazing

a joining process whereby a filler metal or alloy is heated to melting temperature

Welding

a fabrication process that joins materials, usually metals, or thermoplastics by causing coalescence

• often done by melting the work pieces and adding a filler material to form a pool of molten material that cools to become a strong joint, with pressure sometimes used in conjunction with heat, or by itself, to produce the weld.

Rivet

a mechanical fastener which before it is installed it consists of a smooth cylindrical shaft with a head on one end.

Bolted Connection

Bolts are used to connect the pieces of metals by inserting them through the holes in the metals; at the threaded end, nuts should be tightened.

Structural metal stud framing

refers to the construction of walls and planes using cold-formed steel components.

Metal Furring System

refers to a non-structural metal attachment that is used to hold a finish material.

Metal Cladding

commonly used for non-structural, rain-screen cladding systems, where the priority is to provide protection from the elements as well as a striking external finish