Abstract
Single crystals of selected orientations of copper, silver and gold have been investigated in tensile tests up to 0·97 T/Tm . The ratio of the flow stresses at a high and low temperature for the same dislocation configuration has been measured and the strain rate sensitivity determined by instantaneous strain rate changes. In this way the variation of the temperature dependent part of the flow stress has been studied. The experimental measurements enable values of the activation energy and activation volume to be calculated for the high temperature flow process which has been found to occur.