119 単純せん断と純粋せん断状態における超音波速度変化に及ぼす集合組織と塑性スピンの影響(材料力学III)(オーガナイズドセッション(a)材料力学・材料強度に関する新展開)

Abstract

Although stress and strain states are same in simple and pure shear states, longitudinal wave velocity changes propagating in the plastically deformed medium under simple and pure shear states are apparently different each other as the results of authors' theoretical and experimental research works. The objective of this paper is to discuss the effect on ultrasonic wave velocity changes due to texture and cross slip under simple and pure shear states via finite element polycrystal analysis. First the texture developments under both states are studied and the results suggest the dependence of transverse wave velocity changes on texture in the small plastic deformation range. Next, the multiplicative amounts of intersected slids between primary and secondary slip systems, which relates closely to the amount of cross slip under both states are calculated and the results show that the point defects induced by cross slip are much easier to be introduced under pure shear state than that under simple shear state, this suggests that the point defects induced by cross slip may cause quite different longitudinal wave velocity changes.