Intelligence – Insight – Ingenuity


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)


Elongation (%)


Impact Resistance Charpy (ft.lbf)


Brinell Hardness


Modulus of Elasticity (lbf/m2 x 106)


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)


Thermal conductivity (W/M°C)


Electrical conductivity (% copper standard @ 20°C)


Density (g/cm3)


Freezing range (°C) approx.


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.

HOW can MRT Castings help you?

I want...

New at MRT

MRT's sites on the Walworth Business Park in Andover are now re-opened, following the evacuation yesterday afternoon of the area whilst the amazing Hampshire Fire & Rescue Service dealt with a major incident nearby.  Normal operations at MRT are resuming now, and our site is unaffected.

Read More
Zoller Logo Resized

Purchasing a Zoller Smile420 Tool Pre-Setter has seen an overwhelming improvement in productivity and wasted downtime.

Read More
Colosio Logo2

MRT Castings is delighted to announce the purchase of a new PFO250 fully automated, die casting cell, from Italian manufacturer Colosio.  

Read More