粘结剂对超音速火焰喷涂碳化钨涂层磨粒磨损性能的影响

采用超音速火焰喷涂(HVOF)工艺在35钢基体上制备了WC-10Ni涂层和WC-12Co涂层,研究了镍、钴这两种粘结剂对WC涂层的显微硬度、摩擦系数和抗磨粒磨损性能的影响,采用扫描电子显微镜观察涂层磨损前后的表面形貌,探讨了WC涂层的磨粒磨损机理。结果表明,以HVOF方法制备的2种WC涂层均有较高的显微硬度,WC-10Ni涂层和WC-12Co涂层与SiC砂纸摩擦副之间的干摩擦系数相差不大。2种涂层在低载荷下均有较好的抗磨粒磨损性能,但在较高载荷下WC-12Co涂层的抗磨性明显优于WC-10Ni涂层。2种涂层的磨粒磨损形式主要为均匀磨耗磨损,磨损机理以微切削和微剥落为主。WC-12Co涂层的磨损表面损伤较轻微,综合性能优于WC-10Ni涂层。

Effect of binder on abrasive wear resistance of tungsten carbide coating prepared by HVOF spraying

WC-10Ni and WC-12Co coatings weredeposited on 35 steel substrate by HVOF(high velocity oxygen fuel) spraying process.The effects of Ni and Co as binders on microhardness,friction coefficient,and abrasive wear resistance of WC coating were studied.The surface morphologies of the coating before and after wearing were analyzed by scanning electron microscopy(SEM) and the mechanism of abrasive wear was discussed.The results indicated that both WC coatings prepared by HVOF have high microhardness,and show little difference in friction coefficient when they rub against SiC sandpaper under dry friction condition.Both coatings have good anti-abrasive wear performance at low load,while at high load the WC-12Co coating has obviously better wear resistance than the WC-10Ni coating.Their main abrasive wear form is uniform abrasion wear and the abrasive wear mechanism is mainly micro-cutting and micro-peeling.The surface damage of the WC-12Co coating after wearing is lighter and has better comprehensive performance as compared with the WC-10Ni coating.