663 is an abbreviation, the full name is ZCuSn6Zn6Pb3, which is a kind of bronze containing tin-zinc-lead elements, so it is also called tin-zinc-lead bronze. Lead is actually not solid-soluble in copper-tin alloys, and it is distributed in single-phase and black inclusions. between dendrites. The distribution of lead in the ingot is not easy to be uniform, usually adding a small amount of nickel can improve its distribution and refine the structure. Lead reduces the coefficient of friction of tin bronze, improves wear resistance and machinability, but slightly reduces mechanical properties.
Copper sleeves, sliding bearings, copper bushes and shaft sleeves cast with 663 tin bronze have good wear resistance. They are wear-resistant accessories for hydraulic equipment, roadheaders, mining equipment, aerospace, ship parts, and steel mills. Bronze bushings have been widely used.