Quasi-in-situ study on the crystallographic lattice rotation of tantalum during compression deformation

Abstract

By employing a quasi-in-situ method, we investigated the crystallographic texture evolution process of high purity tantalum during compression deformation. The influence of grain size, aspect ratio, and initial orientations on the crystallographic lattice rotation process was analyzed in-depth using the electron backscatter diffraction technique. It is found that the randomly distributed grain orientations mainly evolve toward {111} and {100} orientations during compression, forming the two typical deformation textures in body-centered cubic metals. Furthermore, the crystallographic rotation direction and degree have no apparent linear relationship with grain size or grain aspect ratio but are mainly related to the grain orientation. Especially, the slight crystallographic rotation angle for {100} grain is primarily associated with the activation of multiple slip systems. Multiple slip systems mean different slip planes and different slip directions, and it is difficult for {100} grains to be dominated by a certain slip system and rotate to a large extent like {111} grains. In comparison, the large crystallographic rotation angle for {110} grain is mainly related to the strain coordination in local regions. {110} grains are easier to active slip systems than grains with other crystal plane orientations inferred from the critical shear stress, thereby the rotation of grains and inhomogeneous deformation occurred during the compression process.

Keywords

• Tantalum
• Crystallographic lattice rotation
• Slip activation
• Strain localization