Bronze

Description

Copper and tin are melted and then atomized using gas to produce alloyed bronze powders. The most common alloys are nominally 90/10, copper/tin, and an alloy containing approximately 2% zinc, 88/2/10, copper/zinc/tin. These powders are atomized in air/gas to produce spherically shaped particles.

Prefixed bronze compositions are produced by physically mixing copper and tin powder. These are typically utilized to produce oil-less bearings. Again, the most common alloy is 90/10, copper/tin, but premixes are made using irregularly shaped copper to provide green strength to the product. By tightly controlling the type of copper and tin used in each unique blend, control over the dimensional change characteristics and sintered product porosity upon sintering can be achieved. Specialized mixes containing graphite are available.

A hybrid manufacturing technique called diffusion alloying makes specialized materials for specialized applications. Micro bearing bronze powder, reduced hour glassing bronzes, and high strength compositions can be produced by mixing copper and tin powder together and subsequently heating the mixture to slightly diffuse the tin into the copper.

Characteristics

• Typically 90% copper and 10% tin alloy or blend
• Custom alloy compositions available
• Typical particle size 100 mesh (<150 µm)
• Apparent density is 2.2 g/cm³ to 4.5 g/cm³
• Pre-mixed powder grades available with controlled dimensional change