Fig. 1(a) shows an original morphology of CuW70 infiltrated sintering alloy. The gray part is W particles and the dark gray
portion is the bonding phase Cu. The longitudinal sectional SEM microstructures of the SFPB-treated specimens are shown in Fig. 1 (c), (e), (g). Comparing to the original morphology of the alloy, it is evident seen that the plastic deformations on the surface are produced after bombardment. The shape of tungsten particles changes from the original ellipsoid to strip or directly into smalle grain. With the increasing depth from the treated surface, the depth of deformation layer are weakened gradually. When the bombardment time is 60 min (Fig. 1(g)), the thickness up to 21 mm. The surface SEM microstructures of the SFPB-treated specimen are shown in Fig. 1(b), (d) and (f). It can be obviously seen that a
part of W particles are fragmented and become smaller on the
surface, the other W particles are extruded and deformed mutually
leading to a number of cracks within the particles, while the