The outstanding characteristics of copper, which apply also to copper P/M parts, are high electrical and thermal conductivities, ductility and corrosion resistance. Many applications of copper and copper alloy P/M parts are based on these characteristics.
Copper powder with a purity of more than 99% copper is available commercially, and parts produced from these powders have electrical conductivities of 80% to 95% IACS as pressed and sintered. Higher conductivities, approaching 100% IACS can be achieved by further densification. High electrical conductivity also means high thermal conductivity. Thus, copper P/M parts have a significant advantage for the production of electronic and electrical components, where electrical or thermal conductivity is an essential attribute.
Copper is a very ductile and malleable metal. Parts produced from copper and copper alloy powders also have excellent ductility. The elongation of pressed and sintered P/M copper, brass and nickel silver parts ranges up to 35% in one inch.
Copper and copper-base alloys are resistant to a wide variety of corrosive environments. P/M parts produced from copper, bronze, brass, nickel silver and copper-nickel have corrosion resistance properties essentially equivalent to those of their wrought or cast counterparts.
The applications of these P/M materials are based on a combination of properties, rather than on a single one. The following case histories indicate that selection is based not only on conductivity, ductility and corrosion resistance but also on strength, ability to hold close tolerances and cost reduction.