Superdislocation dissociation and plastic deformation mechanism of ordered alloys with the L12 structure

Abstract

where T F is the "friction" stress, ~ is the antiphase boundary energy in the slip plane, s is the magnitude of shear in the slip zone associated with the action of the source, ~ is the fraction of dislocations sliding in the maximum shear plane of the zone [5], is obtained for the stress at which dissociation of superdislocations occurs in the effective slip planes at a single dislocation. The distribution of the antiphase boundaries in the effective slip planes is quite nonuniform [5]. Firstly, the rate of antiphase boundary accumulation in the shear zone domains where slip is accomplished by superdislocations of edge orientation is considerably higher than in domains where primarily superdislocations of screw orientation slip. According to the estimates [5], in the case of edge superdislocations q = 2, 3, while in the case of screw superdislocations q = 15.