Computation method of metal's flow stress for electroplastic effect

Abstract

Based on the thermally activated plastic flow concept, a method is presented for calculating the amount of metal's flow stress for electroplastic effect. This calculation method takes into account both the influence of internal local stress field on dislocation slipping velocity and the change of the parameters of the thermally activated rate equation with a current pulse applied. The results not only indicate that the relational expression of the metal's flow stress and current density but also demonstrate the metal's flow stress drop associates with an enhanced plastic strain rate. Moreover, the experimental research on tensile tests of copper wire was carried out. The experimental results show that the computational values are reliable while the current density is lower than 1500 A/mm 2.