Metals

Seite 1

Mild Steel - Ferrous

0.15-0.35% carbon

Properties:

Tough

Ductile

Malleable

High tensile strength

Easily joined

Easily Welded

Poor resistance to corrosion

Cannot be hardened and tempered

General purpose material

Uses:

Nails

Screws

Nuts and Bolts

Girders

Car Bodies

Manufacturing:

Can be easily worked: cut, machined, heated and hammered into shape.

Apart from case hardening cannot be heat treated.

Needs a barrier to stop rust E.G. paint, galvanisation, plastic coating.

Medium Carbon Steel - Ferrous

0.4-0.7% carbon

Properties:

Strong

Hard

Less ductile (than mild steel)

Less tough

Less malleable

Uses:

Garden tools

Springs

Rails

Manufacturing

Can be cut, shaped, machined.

Can be heat treated to alter it's properties.

High Carbon Steel - Ferrous

0.8-1.5% carbon

Properties:

Very Hard

Less ductile

Less tough

Less malleable

Difficult to cut

Easily joined by heat treatment

Strength decreases above 0.9% carbon

Uses:

Hand tools e.g. hammers, chisels, screwdrivers, punches

Manufacturing:

Can be cut, shaped, machined.

Can be heat treated to alter it's properties

White Cast iron - Ferrous

1.7-2.9% carbon

Properties:

Brittle

Very hard

Uses:

Heavy machinery

Manufacturing:

Cannot be machined

Grey Cast Iron - Ferrous

2.5-4.0% carbon

Properties:

Brittle and will shatter if dropped

Corrosion resistant

High thermal conductivity

Strength under compression

Hard skin, brittle soft core

self lubrication

Uses:

Cookware

Disk brakes

Components for machines

Manufacturing:

Can be machined

Easily cast

Cannot be welded

Cannot be bent or forged

Aluminium - Non-ferrous

Properties:

High strength to weight ratio

Lightweight

Soft

Ductile

Work hardens in a cold state

Non- toxic

Good conductor of heat and electricity

Corrosion resistant

Polishes well

Does not withstand great loads

Uses:

Kitchen cooking utensils

Packaging

Cans

Foil

Window frames

Aircraft

Engine Components

Castings

Manufacturing:

Can crack under stress and requires constant annealing when worked.

Difficult to join

Easy to machine

Copper - Non-ferrous

Properties:

Malleable

Ductile

Tough

Good conductor of heat and electricity

Corrosion resistant

Polishes well

Expensive

Uses:

Hot water storage cylinders

Central heating pipes

Electrical wire

Printed circuits

Kettles

Manufacturing:

Suitable for hot and cold working

Easily joined

Solders and brazes well

When worked requires constant annealing

Can be easily cut and machined

Zinc - Non-ferrous

Properties:

Very weak

Poor strength to weight ratio

Extremely resistant to corrosion

Low melting point

Ductile

Expensive

Uses:

Galvanised steel

Castings

Batteries

Rust proof paints

Manufacturing:

Difficult to work

When worked will become brittle

Stainless Steel - Alloy

composition:

Chromium

Nickel

Steel

Properties: