采用等离子喷涂和激光重熔复合工艺在Ti-6Al-4V基体上分别制备了微米和纳米Al2O3-13wt.%TiO2涂层, 通过光学金相显微分析(OM)、扫描电镜分析(SEM)、显微硬度试验等方法研究了激光重熔对涂层的组织及性能的影响。试验结果表明, 激光重熔可消除涂层内部的孔隙和层状缺陷, 获得表面平整、致密的重熔涂层, 且涂层与基体形成了良好的冶金结合。激光重熔后, 微米和纳米Al2O3-13wt.%TiO2涂层的平均硬度值分别由喷涂态涂层的803 HV0.3和846 HV0.3提高至1 111 HV0.3和1 451 HV0.3。

In this paper, microstructured and nanostructured Al2O3-13wt.%TiO2 coatings were prepared on Ti-6Al-4V alloys by plasma spraying and laser remelting. Optical metallographic microscopy (OM), scanning electric microscopy (SEM) and micro-hardness test methods were used to investigate the effects of laser remelting on the microstructure and properties of the coatings. The test results show that the pores and lamella defects of the as-sprayed coatings were eliminated to obtain smooth and dense coatings after laser remelting, and a good metallurgical bonding was formed between the laser-remelted coatings and the substrates. After laser remelting, the average Vickers hardness values of the laser-remelted microstructured and nanostructured Al2O3-13wt.%TiO2 coatings were increased from 803 HV0.3 and 846 HV0.3 to 1 111 HV0.3and 1 451 HV0.3.