Title :
Stress relaxation-influence of composition and conductivity
Author :
Kamf, Anders ; Sundberg, Rolf
Author_Institution :
Metallverken AB, Vasteras, Sweden
Abstract :
Stress relaxation measured at different temperatures up to 175°C for two alloys is discussed. One is conventional phosphor bronze CuSn4 (C511), and the other is a recently developed alloy with nickel addition and lower tin content (CuNi1.7Sn1.2). The CuNiSn alloy has higher modulus of elasticity and higher electrical conductivity. The relaxation tests show that it has better properties, especially at high temperatures. Stress relaxation is very much influenced by the temperature. In an actual connector the temperature rise depends among other things on the conductivity of the material. Connectors of equal design but made of different material therefore reach different temperatures at a certain current. Theoretical calculations of the temperature rise at different current intensities have been performed. When the relaxation data are plotted against current intensities, alloys with higher conductivity reach lower temperatures and therefore show better relaxation properties
Keywords :
copper alloys; electric connectors; materials testing; nickel alloys; phosphorus alloys; stress relaxation; tin alloys; 0 to 175 C; CuNiSn alloy; CuSnP alloy; current intensities; electrical conductivity; material composition influence; material conductivity; modulus of elasticity; phosphor bronze; relaxation tests; stress relaxation; temperature rise; Conducting materials; Conductivity; Connectors; Elasticity; Nickel alloys; Phosphors; Stress measurement; Temperature measurement; Testing; Tin alloys;
Conference_Titel :
Electronic Components Conference, 1989. Proceedings., 39th
Conference_Location :
Houston, TX
DOI :
10.1109/ECC.1989.77736