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PB2

Copper Alloy PB2 (PHOSPHOR BRONZE)

This alloy conforms to BS 1400 PB2

Chemical Composition

	%		%		%
Tin	11.0-13.0	Phosphorous	0.15 min	Lead	0.012-0.02
Nickel	0.5 max	Zinc	0.3m	Copper	Remainder
Impurities	0.15 max

Mechanical Properties


Tensile Strength (N/mm²)	220-310
Elongation (%)	7
Brinell Hardness	69
Modulus of Elasticity (lbf/m² x 106)	12

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. The mechanical properties shown above cannot be used as an indication of performance at elevated temperatures.

Physical Properties


Coefficient of Thermal Expansion (per °C @ 0-250°C)	0.000018.3
Thermal conductivity (W/M°C)	45
Electrical conductivity (% copper standard @ 20°C)	9
Density (g/cm³)	8.8
Freezing range (°C) approx.	1000-831

Machinability

Machinability is good, being a medium hardness alloy. This material gives short turnings.

Corrosion Resistance

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

Application and General notes

General uses include unlined bearings for heavy compressive loads and shock, piston rings, axle boxes, gear wheels, centrifugal castings, and castings which require good wear resistance.