The mechanism of prismatic dislocation loop formation in cyclically strained aluminium

Abstract

Abstract Diffraction contrast theory has been applied to determine the nature of prismatic dislocation loops (i.e. vacancy and/or interstitial type) observed in high purity aluminium foils cyclically strained at 78°K. It has been established that both interstitial and vacancy loops are formed during cyclic straining. It is concluded that the only model of dipole formation consistent with these observations is the Gilman (1962) double cross-slip mechanism as modified by Fourie (1964).