目的 研究纳米颗粒对 Ni 基合金涂层抗热腐蚀性能的影响。 方法 采用压片预置式激光熔覆工艺,制备了纳米 Al₂O₃ 颗粒增强的 NiCoCrAlY 合金涂层,对熔覆层界面区组织及裂纹进行了显微分析,进行了 1000 益 高温熔盐热腐蚀性能试验。 结果 加入纳米 Al₂O₃ 颗粒的激光熔覆涂层界面区未出现明显缺陷,其热腐蚀失重速率远远低于未加纳米颗粒的涂层,腐蚀表面未出现严重的隆起和剥落,腐蚀层深度小。 结论 添加适量纳米 Al₂O₃ 颗粒对 NiCoCrAlY 合金激光熔覆层界面区裂纹的形成有一定的抑制作用,可使熔覆层的抗高温热腐蚀性能明显提高。

Objective In order to study the effects of nanoparticles on the hot corrosion resistance of Ni-based alloys cladding. Methods Nano-Al₂O₃ particles reinforced NiCoCrAlY alloy cladding was prepared using the tabletting preset laser cladding process. The microstructure and interface cracks of cladding layer were analyzed, and high temperature corrosion was performed in the 1000 益 molten salt . Results The results showed that the laser cladding interface region prepared with addition of Al₂O₃ particles did not show obvious flaws, compared to the layer prepared without addition of nanoparticles, its hot corrosion weight loss rate was much lower, its corrosion surface did not show serious uplift and flake, and its corrosion depth was low. Conclusion Addition of appropriate amount of nano-Al₂O₃ particles had an inhibitory effect on the formation of cracks in the NiCoCrAlY alloy laser cladding interface region. And the high temperature corrosion resistance of the laser cladding layer was significantly improved.