HVOF喷涂WC-10Co-4Cr涂层的砂浆冲蚀行为

以2种不同的HVOF喷涂系统和3种商用粉末在0Cr13Ni5Mo基材上喷涂6种WC-10Co-4Cr涂层,用自行研制的料浆罐冲蚀设备对涂层和基材的砂浆冲蚀行为进行了研究,分析了显微结构和显微硬度对涂层冲蚀性能的影响及涂层冲蚀后的表面形貌.结果表明,在文中试验范围内涂层和基材的冲蚀失重均随冲蚀时间线性增加;各攻角下,WC-10Co-4Cr涂层的耐冲蚀性远远优于0Cr13Ni5Mo不锈钢;除了分层和裂纹明显的涂层,HVOF热喷WC-10Co-4Cr涂层的冲蚀失重表现出对攻角不敏感的特征.涂层的冲蚀机制为粘结相的微切削和涂层片状剥落,低攻角下的剥落坑面积大而浅,高攻角时面积小而深,片状剥落的程度随涂层气孔率的增加而增加.

Slurry Erosion Behavior of HVOF Sprayed WC-10Co-4Cr Coatings

Two different HVOF spray systems were used to prepare six WC-10Co-4Cr coatings on 0Cr13Ni5Mo stainless steel using three commercial powders, and the slurry erosion behavior of coatings and the substrate was investigated on a self-manufactured slurry pot erosion tester. The influence of microstructure and micro-hardness on the erosion performance of coatings and the surface morphology of coatings after erosion were also analyzed. The results indicated that, the erosion mass loss of the coatings and the substrate in this work all increased linearly with the increase of erosion time; the erosion resistance of WC-10Co-4Cr coatings was much better than that of 0Cr 13Ni5Mo stainless steel regardless of different impact angles; the erosion mass loss of HVOF sprayed WC-10Co-4Cr coating showed that the crack was insensitive to the impact angle. The erosion mechanism of coatings included micro-cutting and detachment of spalls, the crater due to detachment was large and shallow under low impact angle, small and deep under high impact angle, the extent of detachment increased with the increase of coating porosity.