Quench-Induced Defect Structure in Al-6.5-at.% Zn

Abstract
The defect structure induced in Al-6.5-at.% Zn upon quenching consisted of homogeneously nucleated dislocation loops, helical dislocations developed from screw dislocations, the latter being introduced by two different processes. The defect structure also contained perfect loops converted from helical dislocalocations and faulted dislocation loops whose nucleation was enhanced by vacancies generated by quench deformation. Based on experimental evidence, a model is presented explaining the formation of a row of perfect dislocation loops from a single helical dislocation. The interrelation of the various types of induced defects is shown by correlating their formation with the aid of vacancy mechanisms.