Some features of the formation and destruction of dislocation barriers in intermetallic compounds: I. Theory

Abstract

A new concept of the possibility of thermoactivated blocking of superdislocations in the absence of external stresses is suggested. A factor that is related to the internal structure of a superdislocation and initiates its blocking due to the creation of a certain effective force has been revealed. Irrespective of the way in which the rearrangement of the superdislocation occurs and of the fine details of the barrier structure, the role of the above factor is determining. Conditions have been formulated under which the formation of barriers becomes possible without loading after a preliminary deformation while their destruction becomes impossible. Based on an analysis of slip on the cubic system, factors have been clarified that are responsible for the ambiguousness of the attempts of restoring the energy of antiphase boundaries from the width of superdislocations in some cases. The mechanisms of dislocation blocking in intermetallic compounds and semiconductors are compared.