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利用横流CO2激光器在钛合金表面制备出原位自生TiB体系陶瓷增强Co基复合涂层,以改善材料表面的综合性能。分析表明,涂层中存在β-Ti,γ-Co,TiB和TiB2陶瓷硬质颗粒相,以及Co2Ti硬质相。利用扫描电镜(SEM),电子探针微区分析(EPMA)对涂层微区组织结构进行研究。结果表明,涂层中原位生成的TiB2和TiB陶瓷颗粒相均匀分布在γ-Co基合金涂层中。随着Ti,B含量的增加,激光熔覆原位生成物的组织形态发生相应的变化,熔覆区组织由细小分散的片状和块状转变为柱状枝晶组织,取向规则,分布均匀。通过摩擦磨损实验对涂层的耐磨性进行评价,发现激光熔覆后涂层磨损量仅为基体材料的1/10左右,耐磨性得到显著改善。
The cross-flow CO2 laser was used to prepare the in-situ TiB system ceramic reinforced Co-based composite coating on the surface of titanium alloy to improve the overall performance of the material surface. Analysis shows that there are β-Ti, γ-Co, TiB and TiB2 hard phase in the coating, and Co2Ti hard phase. The microstructure of coatings was investigated by scanning electron microscopy (SEM) and electron probe microanalysis (EPMA). The results show that the TiB2 and TiB ceramic particles formed in situ in the coating are uniformly distributed in the γ-Co-based alloy coating. With the increase of the content of Ti and B, the morphology of laser cladding in-situ products changed correspondingly. The microstructure of the cladding zone changed from finely dispersed flake and block into columnar dendritic structure with regular orientation and uniform distribution. The abrasion resistance of the coating was evaluated by the friction and wear test. It was found that the abrasion loss of the coating after the laser cladding was only about 1/10 of that of the base material, and the wear resistance was significantly improved.