Simulation on the deformation behaviors of nanotwinned Cu considering the angle effect between loading axis and twin boundary

The effect of the angle θ between loading axis and twin boundary (TB) on the deformation behaviors of nanotwinned Cu was studied by finite-element method (FEM) under tensile deformation. Three different microstructures ( θ ¯ = 30 ° , σ ¯ = 3.7 ; θ ¯ = 10 ° , σ ¯ = 3.7 and θ ¯ = 30 ° , σ ¯ = 8.8 ) were presented. Evolution of equivalent plastic strain showed that the deformation of the three microstructures were distinct on account of θ: the grains with larger θ deformed first; compared with the microstructure with θ ¯ = 10 ° , σ ¯ = 3.7 , the microstructure with θ ¯ = 30 ° , σ ¯ = 3.7 can effectively delay the onset of shear band. The results demonstrated that an unusual combination of high strength and ductility can be obtained by making a proper arrangement of θ. However, the effect of θ on the stress–strain relations was weakening as twin density lamellae thickness decreases.