A Study of Low-Temperature Creep in Aluminium by Change-in-Stress Experiments: Thermal Activation of Attractive Junctions

AbstractLow-temperature creep in aluminium has been studied by means of change-in-stress experiments. The value of the flow parameter B (= ∆ ln έ/∆τ) was higher for creep following stress decrements than that for creep following increments, the difference being negligible at higher stresses. Among the various possible mechanisms considered, a model based on the formation of attractive junctions following a stress decrement, causing a change in the number of dislocation elements participating in the activation event, explains the effect satisfactorily.