The range of metals are classified as ferrous and non ferrous.
Metals can then be separated under alloys and non alloys.
Ferrous metals- Metals that contain iron and carbon.
Non ferrous- metals that do not contain iron.
Ferrous alloys- A mixture of two or more metals. At least one of which contain iron and carbon.
Non ferrous alloys- A mixture of two or more metals. Non of them containing iron and carbon.
Mild steel- Quite strong and cheap, rusts easily. Cant be hardened or tempered.
- Car bodies
- Nuts and bolts
High carbon steel- Harder than mild steel and can be hardened and tempered. Difficult to work with and rusts.
- Drills
- Tiles
- Chisels
- Saws
Cast iron- Hard, however brittleorder impact.
- Machine parts
- Brake disks
- Engines
Non- ferrous metals
Aluminium- Light weight and corrosion resistant. Expensive and not nearly as strong as steel.
- Aeroplanes
- Cars
- Ladders
Brass- Quite strong, corrosion resistant, malleable, ductile and looks good.
- Door furniture
- Electrical parts
Copper- Relative soft, malleable and ductile and a very good conducter of electricity.
- Wires
- Pipes
Ferrous alloys
- Stailess steel
- High speed steel
- Die (tool) steel
Non ferrous
- Brass
- Bronze
- Duraliumin
Non ferrous
- Brass
- Bronze
- Duraliumin
Where does metals come from ?
Gold is the only metal that is extracted and usable without processing. All other metals and found as ores.
Common metals ores
- Iron- Magnnetite, heamatite
- Copper- Chalcopyrite
- Tin- Cassiterite
- Aluminium- Bauxite
- Lead- Galena
- Zinc- Zinc blende
25% of the earth crust is made of ores. the more rare, the more expensive it is. Aluminium is the most common.
Iron is converted from its ore by heating. The resulting impurities (slag) are removed from the furnace leaving a soft greyish metal once it has cooled. Iron is rarely used without combining it with carbon, gibung it a greater strength. The result in this combination is steel.
Steel- Iron and carbon. The amount of carbon determines on the strength. Alloymy increases properties- toughness and corrosion.
Carbon- found in the earth and is made up of coal and diamond. Amount of carbon in steel determines strength and hardens BUT increases how brittle.
More carbon= more hardness/ less dutcile/ more brittle.
Non ferrous metals doesnt contain iron.
Metals Melting point (degrees) Uses
Aluminium 660 Saucepans and kitchen tools
Copper 1083 Water and gas pipes- wire
Gold 1063 Jewellery
Lead 330 Construction, roofing
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