Si_3N_4球/DLC膜摩擦副在真空环境下的摩擦学行为研究

Tribological Property in Vacuum of High Speed Steel Modified with Diamond-Like-Carbon Coatings

采用非平衡磁控溅射技术在高速钢基体上制备了类金刚石(DLC)膜。采用球盘式摩擦磨损试验机考察了DLC膜在大气和真空环境干摩擦条件下的摩擦学性能,并比较分析了GCr15钢球和Si3N4球不同摩擦配副对DLC膜的摩擦学性能。采用光学显微镜及扫描电镜观察了摩擦副的磨损表面形貌。研究结果表明:由于转移膜的形成Si3N4球/DLC膜摩擦副在大气下具有良好的摩擦学性能;而在真空条件下摩擦副易发生明显的粘着磨损,使摩擦系数、磨斑增加,磨损表面上存在着较多的片状磨屑和微米级颗粒。

The diamond-like-carbon（ DLC） coatings were deposited on substrate of high speed steel by unbalanced magnetron sputtering. The tribological properties of the DLC coatings against GCr15 and Si3N4 balls were investigated in vacuum and in ambient environment,respectively. The microstructures of the worn surfaces involved after ball-on-disc friction and wear tests were characterized with scanning electron microscopy. The preliminary results show that the DLC coating significantly reduces the friction coefficient and improves the surface hardness and wearresistance in air and in vacuum. In addition,the friction coefficient of the DLC coated substrate against GCr15 steel and Si3N4 balls in air was found to be lower than that in vacuum,possibly because of the adhesive wear,as shown by the rough wear-tracks,micro scraps and grains left by the test on the surfaces of DLC coatings and balls.