Appendix: Properties ofengineering metals

The following are the properties of the important engineering metals.

Metal Relative Melting Tensile Elottg. Characteristics and usesdensity point C strength %

MPa

Aluminium

Antimony

Beryllium

Cadmium

Chromium

Cobalt

Copper

Gold

Iron

Lead

Magnesium

Manganese

Mercury

Molybdenum

Al

Sb

Be

Cd

Cr

Co

Cu

Au

Fe

Pb

Mg

Mn

Hg

Mo

2.7

6.6

1.8

8.6

7.1

8.9

8.9

19.3

7.9

11.3

1.7

7.2

13.6

10.2

660

630

1285

321

1800

1495

1083

1063

1535

327

651

1260

-39

2620

59

10

310

80

220

250

220

120

500

18

180

500

60

0

2.3

50

0

6

60

30

10

64

5

20

Liquid at ordinarytemperatures.

420 50

Nickel Ni

Niobium Nb

8.9

8.6

1458

1950

310

270

28

49

The most widely used of the 'light metals'. Common inthe Earth's crust.A bright, crystalline metal, used in limited amounts inbearing and type-metals.A light metal, the use of which is limited by its scarcity.Used in beryllium bronze and nuclear-power industries.Used for plating steel, and to strengthen copper fortelephone wires.A metal which resists corrosion, and is therefore used forplating and in stainless steels.Used mainly in permanent magnets, in super-high-speedsteels and corrosion-resistant 'super-alloys'.Now used mainly where very high electrical conductivityis required; also in brass and bronzes.Of little use as an engineering metal, because of softnessand scarcity. Used mainly in jewellery, and as a system ofexchange.Quite soft when pure, but rarely used in engineering inthe unalloyed form. As steel, our most important metal.Not the densest of metals, as phrase 'as heavy as lead'suggests. Very resistant to corrosion - used in chemicalengineering, but main uses in batteries and pigments.Used in conjunction with aluminium in the lightest ofengineering alloys.Very similar to iron in many ways - used mainly as adeoxidant and desulphuriser in steels.The only liquid metal at normal temperatures. Used in'mercury-in-glass' thermometers and scientificequipment.A heavy metal, used mainly in alloy steels. One of themain constituents of modern high-speed steels. Also usedin stainless steels.A very adaptable metal, used in both ferrous and non-ferrous alloys. The metallurgist's main 'grain refiner'.Principal uses - stainless steels and electroplating.Also known as 'columbium' in the USA. Used mainly inalloy steels and in high-temperature alloys.

Appendix: Properties of engineering metals 391

Metal Relativedensity

Meltingpoint C

TensilestrengthMPa

Elong. Characteristics and uses

Platinum

Tungsten

Pt 21.4 1773 130

W 19.3 3410 420

35

Silver

Tin

Titanium

Ag

Sn

Ti

10.5

7.3

4.5

960

232

1667

140

11

230

50

60

55

16

UraniumVanadiumZinc

Zirconium

UVZn

Zr

18.75.77.1

6.4

11501710420

1800

390200110

220

43825

25

A precious white metal. Used in scientific apparatus,because of its high corrosion-resistance, also used in somejewellery.Has the highest electrical conductivity, but is used mainlyin jewellery and, in a few countries, for coinage.Widely used but increasingly expensive. 'Tin cans' carryonly a very thin coating on mild steel. Very resistant tocorrosion. A constituent of bronze.A fairly light metal, which is becoming increasinglyimportant as its price falls due to the development of itstechnology.Used in electric light filaments, because of its highmelting-point. It is also the main constituent of most high-speed steels and heat-resisting steels, but its main usenow is in cemented carbides.Now used mainly in the production of atomic energy.Used in some alloy steels as a hardener.Used widely for galvanising mild- and low-carbon steels.Also as a basic for some die-casting alloys. Brasses arecopper-zinc alloys.Used as a grain-refiner in steels. It is also used for atomicenergy applications.