Copper Based Alloy Casting from the Butler Foundry

Copper Based Alloy

Cast copper based alloy is very versatile and offer the casting buyer a range of benefits over other metals. They are easily cast and can achieve a range of physical and mechanical properties. They are easily machined, brazed, soldered, polished or plated.

The following list identifies the key physical and mechanical properties. Although not every property is applicable to every alloy, as a group, copper based alloys are diverse in their applications and unique to other alloy groups.

• Good corrosion resistance, which provides durability and long term cost effectiveness. Copper based alloys are particularly suited to plumbing fixtures and other aquatic uses such as impellers, and pump housings.
  
• Bio-fouling resistance, as copper inhibits marine organism growth. Although this property (unique to copper) decreases upon alloying, it is retained at a useful level in many alloys.
  
• Wide range of mechanical properties. Copper in its pure form is soft and malleable. When alloyed to form high tensile brass its properties change to create a material of much greater strength and hardness.
  
• High thermal and electrical conductivity, which is greater than any metal except silver. Although the conductivity of copper drops when alloyed, copper alloys with low conductivity still conduct both heat and electricity better than other corrosion-resistant materials.
  
• Low friction and wear rates. Copper based alloy bushes and bearings exhibit lower wear rates than steel.
  
• Excellent cast ability across the range of casting processes.
  
• Excellent machinability particularly in those alloys containing lead, as the lead acts as a natural lubricant.
  
• Ease of post cast processes such as polishing, brazing, plating and welding.
  
• Wide range of alloys providing the casting buyer with the unique ability to match his precise requirements to a particular alloy.
  
• Low cost castings due to the ease of machining, and surface finishing compared to other metals.
  

Copper based alloys provided by W H Butler & Sons (Founders) Ltd.

Butler's foundry has been casting copper based alloy since its conception as a casting producer as far back as 1922. All alloys are sand cast using either the green sand or air set process. All alloys conform to BS1400.

Phosphor bronze Pb1, Pb2, Pb3

Generally used for bearings, gear wheels, springs and general coppersmithing.

Leaded phosphor bronze Lpb1

This being a leaded phosphor bronze it is suitable for a wide range of bearings. It can also be used for valves, high-pressure steam fittings, general duty bushes.

Gunmetal G1

A composition with good resistance to corrosion, which is also standard admiralty gunmetal. It can be used for high load, low speed bearings, high-pressure pipefittings, and also a certain amount of hydraulic castings.

Leaded Gunmetal LG2

A material with excellent machining characteristics, good casting qualities and moderate strength. Particularly suitable where pressure tightness is required.

Leaded Gunmetal LG4

When cast is not so sensitive to changes in section as LG2 and is also suitable where thick wall sections are incorporated. Is often used for high-pressure valves where liquid oxygen and nitrogen are present. Hydraulic pressure and centrifugal pump castings.

Aluminium Bronze AB2

Has excellent bio fouling resistance and corrosion resistance. Used for acid resisting pump parts and marine use.

High Tensile Brass HTB3

A high tensile brass with good corrosion resistance but is liable to stress corrosion cracking when used in marine and salt-water conditions. It is mainly used for large nuts and similar threaded components.