Tensile deformation mechanism in pure copper subjected to surface mechanical attrition treatment

The ambient tensile deformation characteristics of copper subjected to the surface mechanical attrition treatment (SMAT) was investigated by means of the electron channeling contrast in scanning electron microscopy (SEM-ECC). It was found that during tensile the shear bands were the common deformation characteristics in nano-grained layer, submicro-grained layer and transition layer formed by dislocation cells. The morphology of the shear bands slightly varied in the surface layer with different structures. The shear bands both in nano-grained layer and submicro-grained layer were formed as a result of the shear sliding along a planar interface. The tensile deformation in transition layer mainly occurred in a scale of the original grains. The shear bands were formed basically according with the rule of crystallography.