Effect of pre-strain direction on energy storage process during tensile deformation of polycrystal

Abstract

Abstract The energy storage process is characterised by the energy storage rate d e s /d w p as a function of plastic work w p or of plastic strain e P ( e s is stored energy). At the initial stage of plastic deformation the dependence of d e s /d w p on e P has a maximum. The present work is devoted to the experimental verification of a hypothesis that the maximum of d e s /d w p can be related to the internal micro-stresses caused by incompatible slip in grains of different orientation. The verification needed two groups of specimens in which the influence of internal micro-stresses on the energy storage rate is different. This requirement was achieved using specimens pre-strained in different directions. Experiments that make it possible to estimate the influence of internal micro-stresses on the rate of energy storage are presented. The obtained results confirm the hypothesis.