【摘要】 由超音速火焰喷涂(HVOF)制备的碳化钨金属陶瓷涂层,具有接近完全致密、结合强度高、硬度高等优势。本文综述了金属表面HVOF碳化钨金属陶瓷涂层疲劳寿命的研究现状,并分析了产生疲劳裂纹的原因,影响疲劳寿命的原因有涂层与基体的性能差异、喷砂引入的缺陷、残余应力及涂层制备工艺等。改进措施有涂层设计、基体不做喷砂或喷丸替代等改变前处理工艺、获得或提高涂层压应力、减少碳化物的分解、合理的工艺参数(如高的速度)、合适的涂层厚度、选用高含量粘结物的碳化钨金属陶瓷粉末、合适的涂层后处理方法等。更多还原

【Abstract】 High velocity oxygen fuel(HVOF) sprayed WC cermet coating possesses high hardness, high bonding strength and nearly full-density, which are the candidates of EHC(electrolytic hard chromium). In the present paper, the research status quo of the influence of HVOF sprayed WC coating on the fatigue life of the substrate was summarized and the reasons of crack initiation and fatigue life decrease were also analyzed. The factors affecting the fatigue life are as follows: the difference between the coating and the substrate in properties, the defects introduced by grit blasting, residual stress and coating preparation. The improvement measures include coating gradient design, change of the pre-treatment such as shot peening replacing grit blasting, obtaining or increasing the coating compressive stress, reducing the decomposition of carbide, reasonable process parameters(such as high speed), proper coating thickness, applying WC powder with high content of binder,appropriate post-treatment of the coating.更多还原