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LG2

Copper Alloy LG2 (GUNMETAL)

This alloy conforms to BS 1400 LG2

Chemical Composition

	%		%		%
Tin	4.0-6.0	Zinc	4.0-6.0	Lead	4.0-6.0
Nickel	1.0	Copper	Remainder

Mechanical Properties


Tensile Strength (N/mm²)	185
Elongation (%)	12
Impact Resistance Charpy (ft.lbf)	19
Brinell Hardness	55-65
Modulus of Elasticity (lbf/m² x 106)	11

Strength at elevated temperatures

Service at elevated temperatures is limited by resistance to gradual deformation over prolonged periods of time and to oxidation. It is not suitable for sustaining loads at temperatures exceeding 300°C.

Physical Properties


Coefficient of Thermal Expansion (per °C @ 0-250°C)	0.000018
Thermal conductivity (W/M°C)	71
Electrical conductivity (% copper standard @ 20°C)	15
Density (g/cm³)	8.8
Freezing range (°C) approx.	1010-854

The machinability of LG2 is excellent. The high lead content gives fine turnings with light cutting load and very good machining characteristics.

Corrosion Resistance

This alloy finds wide application where good corrosion resistance is required.

Application and General notes

This alloy is a very useful all-round alloy and has been known for many years as 'ounce' metal and also as 'red brass'.

Applications include bearings, for backings only and general application, pressure castings (for normal temperatures up to 200 lbs. p.s.i., and steam pressures up to 100 lbs. p.s.i. up to 260°C), and pressure-tight castings. It also suits wide applications for general castings where moderate strength, pressure tightness and good machinability are required, for example fire equipment fittings, hose couplings, water pump impellers and small gears.