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在Ti-6Al-4V合金表面激光熔覆NiCrBSi-TiC复合涂层,利用扫描电镜和透射电镜分析了熔覆层的微观组织,测试了熔覆层在大气和真空(P=10~(-5)Pa)环境中的摩擦磨损性能。结果表明,熔覆层的组织是在γ-Ni树枝晶和γ-Ni+M_(23)(CB)_6共晶的基体上弥散地分布着未熔TiC颗粒和液析TiC。未熔TiC颗粒与基体γ-Ni之间具有外延生长的结合界面,液析TiC与基体γ-Ni结合界面干净、光滑。熔覆层在大气环境中的摩擦系数在0.3～0.4之间,磨损率比Ti-6Al-4V合金降低约一个数量级,在真空环境中的摩擦系数在0.4～0.5之间,磨损率比Ti-6Al-4V合金降低约一倍。
The NiCrBSi-TiC composite coating was laser cladding on the surface of Ti-6Al-4V alloy. The microstructure of the coating was analyzed by scanning electron microscopy and transmission electron microscopy. The microstructure of the coating was tested under atmospheric and vacuum conditions (P = 10-5 ) Pa) environment of the friction and wear properties. The results show that the microstructure of the coating is dispersed in the matrix of γ-Ni dendrites and γ-Ni + M_ (23) (CB) _6 eutectic with unmelted TiC particles and liquid-phase TiC. The interface between the unmelted TiC particles and the matrix γ-Ni has an epitaxial growth interface. The interface between the liquid-phase TiC and γ-Ni matrix is clean and smooth. The friction coefficient of the cladding layer in the atmosphere is between 0.3 and 0.4, the wear rate is about one order of magnitude lower than that of the Ti-6Al-4V alloy, and the friction coefficient in the vacuum environment is between 0.4 and 0.5. The wear rate is lower than that of the Ti- 6Al-4V alloy reduced by about double.