Fig. 3 shows the TEM images and SAED patterns of SFPB-treated CuW70 alloy. A large number of dislocation lines and dislocation tangles are formed in the SFPB-treated CuW70 alloy sample, whose distribution is very unevenly, as seen in Fig. 3(a). The density of dislocation is very high in some local area. The sharply increasing of micro-stain leads to the proliferative dislocations after plastic deformation of surface. With further straining, the dislocations continue proliferation, rearrangement, resulting in further generation of dislocation tangles in the interior of grain.