Metals

Ferrous metals- Contain iron

Non Ferrous metal- Dont contain iron

Pure metals

Ferrous                       Non ferrous

Cast Irons                    Aluminium

Steels                          Copper

Mild steel                     Lead

M carbon steel             Tin

High carbon steel         Zinc

Metal Alloys

Ferrous                     Non ferrous

Stainless steel          Brass

High speed steel       Bronze

Die steel

Structure of metals

• Made from crystals

As a metal is worker the crystals fracture becoming smaller and more tightly compact together= makes metal harder- called work hardening

Ferrous metals

Iron

• Directly from its ore through the use of a blast furnace, the impurities(****) are removed leaving soft, grey metal, known as 'pig iron' - Not very high quality
• Generall soft and ductile
• When carbon is mixed with iron the characteristics are greatly improved- steel
• The amount of carbon in iron makes different types of steel
• Each type has different properties of strength and hardness:

- Low carbon steel

-Medium carbon steel

-High carbon steel

-Cast iron

Mild steel- Nuts and bolts, washers, car bodies and white goods(panels)

Medium carbon steel- Springs, general gardening tools

High carbon steel- Hand tools, scribers, chisels, plane blades

Cast iron- Machine parts, brake disks, engines

High speed steel- Drill bits

Non ferrous- dont contain iron

Examples- aluminium, copper, lead, zinc, tin, silver, gold and platinum

Aluminium is difficult to process and consumes a large amount of energy- makes it a costly process

Copper expensive as crushed a refined to remove all unwanted ores

Aluminium

• Lightweight and has high resistance to corrosion
• Drinks cans and aluminium foils
• Excellent conductor of electricity

Copper

• Malleable, good conductor of heat
• Cables and wires
• Central heating and water pipes

Gold

• High melting point
• Jewellery
• Electronics- sim cards, cable adaptors

Lead

• Low melting point
• Very soft but very heavy
• Roofing as good resistance to corrosion

Platinum

• High melting point
• Precious metal in jewellery

Silver

• Melting point of 960 degrees
• Expensive cutlery

Tin

• Rarely used in pure state
• Food wrapping

Titanium

• High melting point
• Good strength to weight ratio
• Clean material
• Surgical applications and spectacle frames

Zinc

• Coating material
• Lock mechanisms and small gears