CXXXI. Effect of temperature on the flow stress of work-hardened copper crystals

Abstract

Changes in the flow stress of copper crystals due to changes in the temperature of deformation have been measured over a range of strains and temperatures. After correction for the effect of temperature on elastic constants the flow stress proves to be insensitive to temperature from 90°k to 180°k, falls rapidly with increasing temperature from 180°k to 250°k, and is virtually constant from 250°k to 473°k (the highest temperature examined). The change of flow stress with temperature is closely proportional to the flow stress itself. These results are discussed briefly in terms of recent ideas of dislocation processes sensitive to temperature. The effect of increasing the temperature of deformation is to produce a yield drop, similar to those observed in aluminium crystals during work softening.