TEMPERATURE-DEPENDENCE OF YIELD STRESS AND WORK-HARDENING IN SPINODALLY DECOMPOSED CU-10NI-6SN ALLOY

The temperature dependence of yield stress and the activation volume during plastic deformation of Cu-10 wt.% Ni-6 wt.% Sn alloy were measured. The incremental yield stress of an aged alloy compared with an as-quenched alloy showed little temperature dependence and the activation volume showed no marked difference between aged and as-quenched specimens. The work-hardening rate up to 10% plastic strain was essentially independent of the heat treatment of the alloy. These results confirm that the internal stress barrier caused by decomposition is too large for glide dislocations to overcome thermally. The observed activation volume is interpreted as a consequence of solid solution hardening. © 1979.