The Effects of Shear Bands on the Rolling Texture Development in 70/30 Brass

Abstract

Texture development and deformation structures in rolled polycrystalline 70/30 brass have been studied. Deformed structures of grains in the polycrystalline samples are classified roughly into two groups; slip deformation and mechanical twinning followed by shear banding. The texture development is characterized by the following three stages.
(1) \lesssim40% reduction. Slip or twinning deformation operates depending on the orientations of grains, and leads to the development of the intermediate type texture. (2) 40∼80% reduction. Shear bands are induced in the grains deformed by mechanical twinning. The twined grains having RP\varparallel{112}∼{135} orientations in the intermediate texture rotate toward the RP\varparallel{111} orientation due to the formation of shear bands, and a texture component of {111}⟨uvw⟩ is formed. (3) \gtrsim80% reduction. Two families of shear bands disposed symmetrically with respect to the rolling plane normal are induced in the twined grains, and the shear bands grow markedly. As a result, a texture component of RP\varparallel{011} develops at the expence of the RP\varparallel{111} component. On the other hand, the RP\varparallel{011} component also develops by slip rotation in the grains unfavorable for twinning. It is concluded that the development of a brass type texture may be correlated with the shear bands formation in the twined grains.