In the present study, reinforced hydroxyapatite (HA) coatings (HA + 10 wt% Al₂O₃ and HA + 10 wt% ZrO₂) were deposited on SS-316 L substrate with an intermediate layer (bond coat) of zirconia by vacuum plasma spray technique. The so-formed reinforced HA coatings were heat treated at 700 °C for 1 h. The influence of post coating heat treatment on phase composition, microstructure, mechanical and electrochemical corrosion properties were investigated. As-sprayed and heat treated coatings were characterized by x-ray diffraction, scanning electron microscope, surface roughness, porosity and crystallinity. Results showed that after post coating heat treatment, the structural integrity of HA has been completely re-established. Moreover, significant drop in porosity has been observed due to the sintering effect produced by heat treatment. Considerable improvement in nanohardness and shear strength was witnessed; however, the nanohardness of top layer was decreased after annealing due to the weak bonding of partially melted and un-melted particles with fully melted splats caused by diffusion process. As-sprayed coatings exhibited higher wear resistance compared to heat treated coatings. Nevertheless, post coating heat treatment effectively enhanced the corrosion resistance of coatings, since, the heat treatment lead to densification of coatings microstructure which further reduces the active sites for dissolution.

在本研究中，增强羟基磷灰石（HA）涂层（HA + 10 wt％Al ₂ O ₃和HA + 10 wt％ZrO ₂通过真空等离子喷涂技术将其沉积在具有氧化锆中间层（粘结涂层）的SS-316 L基板上。将如此形成的增强HA涂层在700°C下热处理1 h。研究了后涂层热处理对相组成，显微组织，机械和电化学腐蚀性能的影响。通过X射线衍射，扫描电子显微镜，表面粗糙度，孔隙率和结晶度表征喷涂和热处理的涂层。结果表明，在涂层后热处理后，HA的结构完整性已完全重建。此外，由于热处理产生的烧结作用，已经观察到孔隙率显着下降。观察到纳米硬度和剪切强度有显着提高；然而，退火后，顶层的纳米硬度降低，这是由于扩散过程导致部分熔融和未熔融的粒子与完全熔融的板片之间的弱结合所致。与热处理的涂层相比，喷涂后的涂层表现出更高的耐磨性。然而，涂层后热处理有效地提高了涂层的耐腐蚀性，因为热处理导致涂层微观结构的致密化，这进一步减少了溶解的活性部位。