Alloys

Steel

alloy of iron and carbon

content of carbon in steel

0.02 to 2%

Elements added to steel

• Chromium

• Molybdenum

• vanadium

• manganese

Effect of chromium addition

corrosion resistance

increased hardness

improved strength

better heat tolerance

Effect of Molybdenum addition

improves corrosion resistance, toughness and strength

Effect of Vanadium addition

reduces grain growth

fine grain structure without reducing ductilityE

Effect of manganese addition

improves quenching properties

allowing hardening with reduced crack riskc

composition of cast iron

Iron 95%

carbon 2-4%

traces

Properties of cast iron

easily cast

good compressive strength

easily machined

• self lubricated due to graphite inclusions

Composition of Brass

Copper 60%

Zinc 40%

Properties of brass

non corrosive in water

easily cast and machined

widely used in piping fittings

Composition of bronze

copper 85%

tin 12%

plus others

properties of bronze

corrosion resistant

casts very well

uses of bronze

sculpture statuary

bells

ship propellers

composition of duralumin

Al 90%

Cu 5%

manganese

magnesium

properties of duralumin

adds strength and durability to copper

lightweight

uses of duralumin

major mat in aircraft construction

composition of solder

tin 86%

Cu

antimony

zinc

silver

OR

tin 60%

lead 40%

properties of solder

low mp

uses of solder

electrical soldering

water resistant soldered joints in pipework

Composition of babbit

tin 89%

antimony 9%

copper 2%

properties of babbit

low melting point

relatively soft - will not abrade shafts

hard particle contaminants will embed in babbit metal bearing rather than damaging shaft

uses of babbit

used in large bearings as lining

Composition of sterling silver

silver 92.5%

copper

purpose of sterling silver

mainly decorative

reduces cost

adds hardness

more durable

composition of cupronickel

copper 60%+

nickel

properties of cupronickel and use

highly resistant to seawater corrosion

used extensively in seawater heat exchangers

composition of monel metal

nickel 63%

copper

properties of monel metal

improves strength of nickel

highly corrosion resistant

chemical plant pipework

marine applications

composition of NiChromes

nickel 50%

chromium 20%

molybdenum 3%

niobium 5%

traces

properties of nichromes

austenitic FCC alloys

high T resistance

creep resistant

casts well