G0310102 Evaluation of the Effects of Plastic Deformation on Anisotropy of Elastic Modulus and Microscopic Structure in Metal

Abstract

In this study, the effect of plastic deformation on microscopic structure and anisotropy of elastic modulus in SPCC (Steel Plate Cold Commercial) is investigated. Various plastic strains (0%, 2.5%, 5%, 7.5%, 10%) are applied to annealed SPCC plates, then, specimens for tensile tests are cut out from them. The elastic modulus of 0° and 90° directions are measured by tensile tests. Cyclic loading tests are performed to investigate the influence of the internal frictions caused by movable dislocations in elastic deformation Movable dislocations are quantified by the boundary tracking for TEM micrographs. As a result, the elastic modulus of the maximum principal strain direction (0° direction) and the minimum principal strain direction (90° direction) decrease more than 10% as 10% pre-strain applied. On the other hand, the elastic modulus shows recovery behavior after strain aging and annealing. The internal frictions increase by movable dislocations after plastic deformation. Remarkable anisotropy is not observed in the elastic modulus and the internal frictions. From the above, it is considered the movable dislocations affect the elastic modulus strongly.