Cu/Ni_3Ti原位复合材料的显微组织和力学性能

Microstructures and Mechanical Properties of Cu/Ni_3Ti Composites

通过真空电弧熔炼法制备了Cu/Ni_3Ti原位复合材料。采用X射线衍射仪、扫描电子显微镜、显微硬度计和纳米压痕仪分别测试了Cu/Ni_3Ti原位复合材料的相组成、微观组织形貌、显微硬度和弹性模量。结果显示,Ni_3Ti相在铜基体中呈针状分布,且铸锭边缘与心部平均晶粒直径分别约为1.74和249μm。Cu/Ni_3Ti原位复合材料在时效温度为550℃时的强化效果最佳,此时铜基体与Ni_3Ti相的显微硬度最大值分别达到了174和209。在热处理后,Ni_3Ti相的最大硬度和弹性模量分别达到10.5 GPa和249.7 GPa,远高于Cu基体,Ni_3Ti相是一种理想的增强相。

Cu/Ni3Ti in-situ composite is prepared by vacuum arc melting.The phase composition,microstructure morphology,microhardness and elastic modulus of the composite are measured by using X-ray diffractometer,scanning electron microscope,microhardness tester and nanoindentation,respectively.The results show that Ni3Ti phase is acicular in the Cu matrix.The average grain sizes at the edge and center of the ingot are about 1.74 and 249μm,respectively.The Cu/Ni3Ti in-situ composite have the highest strengthening effect after aging at 550 ℃.Meanwhile,the maximum microhardnesses of Cu matrix and Ni3Ti phase are up to 174 and 209,respectively.After heat treatment,the maximum hardness and elastic modulus of Ni3Ti phase measured by nanoindentation are 10.5 GPa and 249.7 GPa,respectively,which are much higher than those of Cu matrix.Therefore,Ni3Ti is an ideal strengthening phase.