Lead alloys

The material. When the Romans conquered Britain in 43 AD they discov­ered rich deposits of lead ore and started a mining and refining industry that was to continue for 1000 years (the symbol for lead, Pb, derives from its Latin name: plumbum). They used it for pipes, cisterns, and roofs, this last a use that continues to the present day. The biggest single use of lead (70% of the total) is as electrodes in lead acid batteries.

Composition

Pb + 0 to 25% Sb or 0 to 60 % Sn, sometimes with some Ca.

General properties

Density

11300

– 11400

kg/m3

Price

*6.0

– 6.6

USD/kg

Mechanical properties

Young’s modulus

12.5

– 15

GPa

Yield strength (elastic limit)

8

– 14

MPa

Tensile strength

12

– 20

MPa

Elongation

30

– 60

%

H ardnes s—Vickers

3

– 6.5

HV

Fatigue strength at 107 cycles

2

– 9

MPa

Fracture toughness

*5

– 15

MPa. m1/2

Thermal properties

Melting point

183

– 31

°C

Maximum service temperature Thermal conductor or insulator?

*70 – 120 Good conductor

°C

Thermal conductivity

22

– 36

W/m. K

Specific heat capacity

122

– 145

J/kg. K

Thermal expansion coefficient

18

– 32

p, strain/°C

Lead weathers well and is exceptionally durable and corrosion resistant.

Typical uses. Roofs, wall cladding, pipe work, window seals, and flooring in buildings; sculpture and table wear as pewter; solder for electrical circuits and for mechanical joining, bearings, printing type, ammunition, pigments, X-ray shielding, corrosion-resistant material in the chemical industry and electrodes for lead acid batteries.