Brass with good stress relaxation resistance - has silicon and tin content and has structure consisting of at least 90 per cent alpha phase

摘要

The alloy contains by wt. 0.05-2 (0.1-1.0)% Sn and 0.05-3 (0.1-1.5) % Si; with the combined total of Sn + Si being >=0.3%. The alloy also contains 20-34 (20-32), more pref. 26-31 % Zn and the balance in Cu. The alloy has good bend formability and pref. is used in the worked condition, with a grain size of approx. 0.005-0.050 mm. The alloy may additionally contain a grain refining addn. and/or an element to promote easy machining. A single phase alloy consists of 0.05-2.0% Sn, 26-34% Zn or 0.05-2.0% Sn, 0.05-3% Si (with % Sn + % S, >0.3%), 20-34% Zn balance Cu. The alloy is used for spring connectors. Resistance to stress relaxation at elevated temperatures improved by additions of Sn and/or Si. At least 90% alloy is alpha phase and in the worked condition grain size is 0.005-0.05 mm. The preferred alloy contains 0.1-1.0 % each of Sn and Si, 26-31 % Zn balance Cu.