Effects of relaxation and pre-history in the course of plastic twisting

Abstract

Abrasion processing of inter-metallic compound of Fe3Al [21] supplemented by volume processing by SPD [22] has demonstrated complex non-monotonic behaviour of the parameters in the course of treatment including a decrease in the structural order parameter down to almost zero value and a succeeding increase resulting in a stable value capture (see Fig. 2 in [22]). This behaviour can be determined by a joint effect of a temporal delay and relaxation in the course of twisting. The present work reports the study of possible mechanisms of the anomalies. The effect of temporal delay and relaxation on the structural order parameter (OP) in the course of plastic deformation by twisting is theoretically analyzed. It is shown that an anomalous behaviour of the OP modulus takes place. The analysis is based on the Landau-Khalatnikov equation. Account for the prehistory results in emergence of a local maximum at the boundary of the second zone and the third one. Account of the time delay affects the rate of decrease in q(t) within the first zone. The rate of time evolution of the rotation function affects the behaviour of q(t) within the third zone.