In this study, the effect of infiltration temperature and holding time on the microstructure, transformation behaviors and mechanical properties of W-NiTi heavy alloys prepared by infiltration and hot pressing were investigated by SEM, DSC and compression tests. It was found that the average W grain sizes of all the W-NiTi heavy alloys prepared at temperatures varied from 1350 to 1450 ℃ with different holding times were less than 5 µm. The average W grain size was found to increase with increasing sintering temperature and holding time. The morphology of W grain was still polygonal with less growth. The NiTi matrix in these alloys was observed to dissolve up to 8.75 wt% W, significantly less than that of conventional tungsten heavy alloys, which could suppress the growth of W grains and make W grains more stable in NiTi matrix than in NiFe or NiCu matrix. All the W-NiTi alloys exhibited reversible martensite transformation. The stable microstructure and the increasing bonding strength resulted in the increasing of the strength and ductility of the alloys with infiltration temperature and holding time in compression tests.

通过SEM，DSC和压缩试验，研究了渗透温度和保温时间对W-NiTi重熔合金的组织，转变行为和力学性能的影响。结果发现，在1350至1450℃的温度范围内，不同保温时间下制备的所有W-NiTi重合金的平均W晶粒尺寸均小于5 µm。发现平均W晶粒尺寸随着烧结温度和保持时间的增加而增加。W晶粒的形态仍然是多边形的，生长较少。观察到这些合金中的NiTi基体最多可溶解8.75 wt％的W，比传统的钨重合金要少得多，与NiFe或NiCu基体相比，NiTi基体中的W晶粒可以被抑制，并使W晶粒更稳定。所有的W-NiTi合金都表现出可逆的马氏体相变。稳定的显微组织和增加的结合强度导致合金的强度和延展性随渗透温度和压缩时间的保持时间而增加。