Study on the cold rolling deformation behavior of polycrystalline tungsten

Tungsten is paid special attention due to its superior properties, especially in nuclear field. Meanwhile it is suitable for texture simulation investigation of BCC metals and alloys as it's near elastically isotropic. This study investigates the cold rolling deformation texture of polycrystalline tungsten using RS model, in which the stress and strain consistence is realized simultaneously. The texture evolution and effects of deformation parameters, including external as well as internal reaction stress, strain and activation of different slip, on texture during rolling are discussed by comparing the simulated results and reported experimental results in literatures. The results show that, the cold rolling deformation texture could be simulated statistically based on RS model. The accumulation of each reaction stress is different. The up-limit of reaction stress sigma'(12) is found to be medium, meaning that sigma'(12) exerts important effect on texture evolution. Much lower accumulation level of sigma'(13) as well sigma'(23) is displayed, each of which within certain range contributes to the increase of different gamma-fiber texture components. The effect of sigma'(22) can't be ignored during rolling, especially in the case of obtaining {111} < 110 > texture. Regarding the deformation textures of tungsten rolled to true strains of 1.7 and -2.91, {001} < 110 > texture is strengthened with the increasing strain and becomes dominant, implying the easier activation of {112} < 111 > slip systems; gamma-fiber texture is weakened at higher strain, and the formation of {111} < 112 > texture shows significant effect of surface shear stress sigma(13), which is due to the nonnegligible surface friction when rolling at high temperature.