Dislocation loops in quenched aluminium and gold

Abstract

When pure metals are rapidly cooled from temperatures near their melting points, considerable numbers of vacant lattice sites in excess of the equilibrium concentrations may be quenched in. Attempts have therefore been made to interpret the changes in physical properties which arise as the result of quenching, as being due largely to the influence of vacancies. Thus the increase in yield stress (1) has been interpreted in terms of the jogging of dislocation lines already in the crystal (2), the creation of small dislocation loops or stacking faults by the disc-like condensation of the vacancies (3, 4) and the formation of cavities on the dislocations (5). The annealing of electrical resistivity (6) has also been interpreted on the second model (4).