純アルミニウム板の集合組織と成形性に及ぼす片ロール駆動冷間圧延の影響

Abstract

Single roller driving cold-rolling (SRCR) was tried to develop the shear texture component {111}〈110〉 in pure aluminium, and the effect of the process on the texture development, r value and deep drawability was studied. The SRCR process, on the one hand, promotes the shear texture component {111}〈110〉 to some extent, and on the other hand, reduces the development of the pure metal type texture. The higher the reduction in thickness is, the more remarkable the effect of the SRCR process on the textural changes is. The shear texture component {111}〈110〉 almost disappears by subsequent annealing, suggesting that it may be unstable in the recrystallization process. Since the development of rolling texture in the SRCR processed sheets is weak, the recrystallization texture is considerably randomized, leading to \barr=0.8∼0.85 and Δr\fallingdotseq0. As a result, the SRCR processed sheet presents a large increase in the limit drawing ratio and very low earing height, in comparison with the conventionally cold-rolled sheet. It is suggested that perfect or inplane isotropy should be realized to improve deep drawability of aluminium and its alloy sheets, if the preferential development of the {111} texture component were unexpected.