Copper Alloy No. 903 is a cast copper-tin-zinc alloy known also as G Bronze or 88-8-0-4 alloy. It has a good combination of strength and corrosion resistance and is often used in castings subject to liquid or gas pressures. Among its many uses are valves, pumps, bushings and gears. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as casting, heat treating, machining, and joining. Filing Code: Cu-345. Producer or source: Copper alloy foundries.