超声冲击处理提高超音速等离子喷涂Cr3C2-NiCr涂层性能

Cr₃C₂-NiCr涂层是中高温下理想的耐磨、抗氧化、耐蚀涂层,常用于高温下的燃气冲蚀磨损、磨粒磨损、微动磨损、硬表面磨损等场合.文中采用超音速等离子喷涂的方法在CuCrZr合金表面制备Cr₃C₂-NiCr涂层,并采用超声冲击的方法对涂层进行后处理.结果表明,经超声冲击处理后,涂层孔隙率由2.34%降低至1.83%;涂层的平均显微硬度由8.9 GPa提高至9.6 GPa,且硬度分布更均匀;在650℃下进行热震试验,涂层的热震寿命显著提高,热震裂纹的扩展路径也发生了变化.

Properties improvement of supersonic plasma spraying Cr3C2-NiCr coating by ultrasonic impact treatment

For the ideal resistance characteristics to wear, oxidation and corrosion,Cr₃C₂-NiCr coating has been widely used in the gas erosive wear,abrasive wear,fretting wear and hard surface wear under high temperature conditions. In this paper, Cr₃C₂-NiCr coating on CuCrZr was obtained by supersonic plasma-spraying method,and the post-processing ultrasonic impact treatment was utilized to certain coating. The results show that porosity of the coating decreases from 2.34 percent to 1.83 percent,and average micro-hardness of coating increases from 8.9 GPa to 9.6 GPa and hardness distribution becomes uniform. Coating thermal shock life at 650℃ improves markedly; meanwhile, crack path of thermal shock also changes.