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为改进钛合金(Ti6A14V)的耐磨性能,应用脉冲Nd:YAG激光器进行了钛合金表面熔覆(Ti+Al/Ni)+ (Cr_2O_3+CeO_2)复合涂层实验,分析了熔覆层微观组织,测试了熔覆层显微硬度及其在大气环境室温下的摩擦磨损性能。结果表明,熔覆层组织是在细小树枝晶和共晶基体上散布着未熔Cr_2O_3颗粒和白亮球状液析Cr_2O_3,及生成的硬化TiAl陶瓷颗粒增强相。显微硬度明显提高,最高可达1150HV,平均是基材的3～4倍。熔覆层和基材实现良好冶金结合,白亮熔合区宽度为10～20μm。激光熔覆层干滑动摩损的摩擦系数在0．2～0．3之间,磨损率比Ti6A14V标样降低约4～5倍。
In order to improve the wear resistance of titanium alloy (Ti6A14V), a pulsed Nd: YAG laser was used to coat the Ti (Al + Ni) + (Cr 2 O 3 + CeO 2) The microhardness of the cladding layer and its friction and wear properties at room temperature were tested. The results show that the microstructure of cladding layer is composed of fine Cr 2 O 3 particles and white bright spherical liquid Cr 2 O 3 dispersed on fine dendrites and eutectic matrix and the hardened TiAl ceramic particles reinforced phase. Microhardness significantly increased up to 1150HV, an average of 3 to 4 times the substrate. The cladding layer and the substrate are metallurgically bonded, and the width of the white-bright fusion zone is 10 to 20 μm. The friction coefficient of dry sliding friction of laser cladding is between 0.2 and 0.3, and the wear rate is about 4 ~ 5 times lower than that of Ti6A14V standard.