Copper Alloy

Copper is a popularly used ductile metal with excellent electrical conductivity, and also finds extensive use as a thermal and electrical conductor, as a building material, and as an important component of various alloys.

There are numerous alloys of copper with important historical and contemporary uses. Casted copper alloys have high tensile and compressive strength, have good wear qualities when subjected to metal-to-metal contact, are easily machined, have good thermal and electrical conductivity, and high corrosion resistance for maximizing product performance. Some of the widely used alloys are:

• Bronze: An alloy of copper and tin
• Brass: An alloy of copper and zinc.
• Monel/ Cupronickel: An alloy of copper and nickel.

Copper has numerous properties, which makes it useful in various industrial applications. Some of the properties are:

• Malleable
• Ductile
• Good conductor of heat
• Good conductor of electricity-in pure state

Copper in its pure form is quite difficult to cast and is prone to surface cracking, porosity problems, and to the formation of internal cavities. The characteristics of the metal for the purpose of casting can be improved by adding small amounts of elements including silicon, nickel, zinc, chromium, tin and silver.

Copper alloys are used in diverse industrial applications. The metal alloys are used for their different properties that are required in different industries. Some of the areas where the metal and its alloys are used are:

• Industrial castings
• Electronics
• Ship building
• Industrial fittings
• Cookware and flatware
• Biomedical

Followings are the two most popular and widely used forms of copper alloys:

• Cast Copper
• Wrought Copper

Copper casting can be used to produce parts in shapes that cannot be easily attained with fabrication techniques, such as - forming or machining. The composition of copper casting alloys may differ from those of their wrought counterparts for a variety of reasons. Usually casting allows greater latitude in the application of alloying elements, because the effects of composition on cold or hot working properties are not significant.

Most of the copper-base casting alloys that contain tin, lead or zinc have moderate tensile and yield strengths, low to medium hardness, and high elongation. In applications that require high tensile or yield strength, the aluminum bronzes, silicon brasses, manganese bronzes, silicon bronzes and some nickel silvers are used instead. Most of the high strength alloys have good resistance to corrosion and wear.

The properties of castings depend on the size of section and the process of casting.

Copper alloy castings are used in applications, which require superior corrosion resistance, high electrical or thermal conductivity, superior bearing-surface qualities or some other special properties. Some of the common examples include bearings, bushings, gears, fittings, valve bodies, and miscellaneous components for chemical processing applications.

The different techniques used to cast copper and its alloys are -

• Sand Casting & CO2 Process
• Shell Molded Casting
• Die-Casting
• Chill Casting
• Centrifugal Casting
• Continuous Casting
• Other Process (like Precision Investment Casting & Plaster Mould Casting)