銅単結晶の圧延における(513)[\bar121]方位の挙動について

Abstract

The copper single crystals with the (513)[\bar121] orientation which is an ideal orientation of the pure metal type rolling texture of fcc metals were rolled under various conditions. The strain rate dependence of the stability of this orientation during rolling was studied by means of the reflective electron-diffraction analysis of lattice rotation and the slip line observation using replica techniques.The single crystals were rolled such that the rolling direction was (1) normal to the transverse direction (TD) and (2) parallel to the longitudinal direction (LD), referred to undeformed crystals.In the case of the rolling referred to TD, the lattice rotation from (513)[\bar121] to (211)[\bar111] via \simeq(513)[\bar455] was observed independent of the strain rates of 10−1/sec and 102/sec. This orientation changes may be connected with the shape change of the crystal resulting from the deformation. These would seem to indicate that the orientation of (513)[\bar121] is not stable for a single crystal during rolling deformation. In the case referred to LD, on the other hand, the stability of the (513)[\bar121] orientation depended on the strain rates. At the low strain rate rolling (10−1/sec), the initial orientation was retained up to high reductions, while at the high strain rate rolling (102/sec), the lattice rotation toward (101)[\bar121] occured gradually. It was found from the slip line observation that there are no changes in active slip systems and no marked differences in slip band configurations except for the degree of the fragmentation of slip bands, in both strain rates. These results were discussed from the view-point of dislobation structures comparing with the reported models for the formation of the (513)[\bar121] ideal orientation.