Crystallographic orientation dependent fracture behavior in tantalum single crystals

We report crystallographic orientation dependent fracture behavior in tantalum single crystals with the tensile axes oriented close to [100], [110] and [111] directions. Three tantalum single crystals were deformed in quasi-static, uniaxial tension and their fracture surfaces were characterized. To understand different deformation modes and failure mechanisms, crystal plasticity-finite element (CP-FE) simulations were performed. Both experiments and CP-FE simulations showed strong strain localization and shear banding in the similar to[100] specimen, little rotation and profuse necking in the similar to[110] specimen, and significant crystal rotations associated with shear-dominated behavior in the similar to[111] single crystal. In addition, voids were observed in fracture surfaces of similar to[100] and similar to[111] single crystals while the similar to[110] specimen was void-free. The failure processes of these single crystals showed that dislocation boundaries are necessary for void nucleation in pure tantalum. This work demonstrates strong effects of crystallographic orientations in failure behaviors. Published by Elsevier Ltd on behalf of Acta Materialia Inc.

Automated summary

The study investigated the fracture behavior of tantalum single crystals with different tensile axes orientations and found that crystal orientation can affect the deformation and fracture characteristics of the material. Both experiments and simulations demonstrated that different crystal orientations result in varying deformation modes and failure mechanisms.