Alloys C17400 and C17410-New Beryllium Copper Alloys for Connector Applications

AIIoys C17400 and C17410 are the first of a new family of copper base alloys containing relatively small quantities of beryllium and cobalt and offer exceptional performance/cost benefits when compared to other specialty copper alloys. Their mechanical and physical characteristics are described and compared to other copper base alloys. The 0.2 percent offset yield strength has been designed to range from 85 to 125 klbf/inch2 (585-860 MPa). The electrical conductivity is high at 40-60 percent IACS. The resistance to stress relaxation has been evaluated at temperatures up to 200°C (392°F) and is exceptional compared to most other specialty copper alloys. Formabiiity in the good-way direction is excellent if compared with other spring materials at the same strength level. However it is directional as with other heavily cold-worked copper base alloys and this Should be accounted for in new designs. Specific connector applications and actual perfomances are discussed. The advantages of high electrical and thermal conductivity and resistance to stress relaxation at moderately elevated temperatures are highlighted.