MaterialsPreliminary Industrial Technology:Metal and Engineering Technologies
Metals• All metals can be classified as eitherFerrous or Non-ferrous.
Ferrous Metals• These are metals which contain iron. Theymay have small amounts of other metals orother elements added, to give the requiredproperties.• All ferrous metals are magnetic and give littleresistance to corrosion.• They make sparks when you grind them.• Examples are mild steel, cast iron, tool steeland stainless steel.
Non-Ferrous Metals• These are metals which do not contain anyiron.• They are not magnetic and are usually moreresistant to corrosion than ferrous metals.• Examples are aluminium, copper, lead, zincand tin.
Definitions of Properties• StrengthThe measure of how a material withstands aheavy load without breaking.• DurabilityThe measure of withstanding wear and tear.• DuctilityThe length that a material can be stretchedwithout fracturing or cracking.
• MalleabilityThe amount of hammering, pressing andshaping a material can take without breaking.• LustreThe lustre of a metal is how shiny the metal is.• HardnessThe resistance a material has denting,scratching or wearing by abrasion.
Properties and Uses of MetalsMetal Picture Ferrous orNon-FerrousProperties UsesCopperBrassSteelSilverGoldAluminium
Sections & Shapes of Metal• Metals can be purchased in many shapes andforms from flat sheets of various thicknessesto tubing, angle and rod of different shapesand sizes.
Solid SectionsLengths of metal are available inmany shapes or ‘sections’.These include:• Round Rod• Square Rod• Hexagonal Rod
TubeTube is available in the shapes below:• Round• Square• RectangularUses:Tube has many uses. Bikes are usually made from circulartube. Metal tables are often made from square tube. If atable was made from solid metal, it would be very heavyand expensive. Tables made from square or circular tubeare light and cheaper to produce because they are madewith less metal.
Flat BarFlat bar is available indifferent widths andthicknesses.UsesFlat Bar is used for general fabrication, makingstructures and frames.
AngleThe most common type of Angles areat a 90 degree angle and has two legsof equal length.UsesAngles are used for various purposes ina number of industries. Framing is oneof the most common uses for steelangles, but steel angles are also usedfor brackets, trim, reinforcements, andmany other uses.
ChannelChannels are strips of metalthat have been formed intoa "C" or "U" shape orchannel and are thereforeoften referred to as"C Channels" and "U Channels".UsesChannels are used for many applications includingbuilding construction.
I BeamsI beams are strips of metalthat have been formed intoan “I” shape.UsesI-beams are used as major support trusses inbuilding, to ensure that a structure will bephysically sound.
Sheet Metal• Sheet metal is metal that has beenformed into thin and flat pieces.• Many different metals can be madeinto sheet metal, such as aluminum,brass, copper, steel, tin, nickel,titanium, silver and gold.• Thicknesses can vary significantly; extremely thin thicknesses areconsidered foil and pieces thicker than 6 mm are considered plate.Uses• Sheet metal can be cut and bent into a variety of different shapes.Sheet metal has many uses including car bodies, aeroplane wingsand roofs for buildings.
Wire• Wire is usually a cylindrical andflexible rod of metal.• Wire is a versatile metal that isproduced in mild steel, copper,brass, aluminium, galvanised andstainless steel.Uses• Wire has many uses. It is used for making wire rope, fencing,suspension bridges, cages and stringed musical instruments.• It is useful in the making of wire netting and as a fasterning materialto tie pieces of metal together.• Wire can be woven into patterns and twisted into shapes.