scope:

1.1 This specification covers copper-tin alloy (phosphor bronze), copper-tin-lead alloy (leaded phosphor bronze), and copper-tin-lead-zinc alloy (bearing bronze), plate, sheet, strip, and rolled bar. The phosphor bronzes are commonly used for deep drawing into bellows, stamping and forming into spring devices and into terminals and connectors for electrical apparatus, because they combine high strength with high elongation. The leaded phosphor bronzes are used where strength, corrosion resistance, and machinability are required. The bearing bronze is used in bushings, bearings, and load bearing thrust washers. The following alloys are covered:

Nominal Composition, % Previously Copper Alloy Used Desig- UNS No. 2 Copper Tin Zinc Lead nation C51000 95 5 ... ... A1 C51100 96 4 ... ... A C51900 94 6 ... ... C52100 A 92 8 ... ... C C52400 90 10 ... ... D C53400 94 5 ... 1 B1 C54400 88 4 4 4 B2 A SAE Specification CA521 conforms to the requirements of UNS No. C52100.

1.2 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system are not exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in nonconformance with the specification.