表面微织构对WC-8Co在往复摩擦磨损中粘结-扩散磨损特性的影响

Effect of Surface Micro-Texturing on Adhesion-Diffusion Wear Behavior of WC-8Co in Reciprocating Sliding

采用激光表面纹理化在WC-8Co上制备了微沟槽织构,通过往复式摩擦磨损试验对其与Ti6Al4V接触的耐磨性进行分析,并以无表面微沟槽织构的WC-8Co为对比样品,研究了表面微织构对WC-8Co粘结-扩散磨损特性的影响,揭示了摩擦过程中表面微织构的磨损机理.结果表明:WC-8Co上的微沟槽对摩擦接触面具有抗粘结作用,在高接触载荷下,这种效应更为明显.织构表面的抗粘结机制是由微沟槽包裹的碎屑产生的.此外,与无表面微织构的WC-8Co不同,表面织构化的WC-8Co的磨损最初来源于微沟槽边缘的断裂,随后扩展到摩擦表面.这种磨损特性归因于微沟槽边缘的高热载荷和机械应力集中,以及激光加工过程中WC晶粒长大与摩擦过程中粘结剂Co扩散的协同效应.

This study investigated the influence of surface micro-texturing on adhesion-diffusion wear behavior of the WC-8Co and revealed the wear mechanism of surface micro-texturing.The micro-grooved texture was prepared on WC-8Co by laser surface micro-texturing,and its wear resistance in contact with Ti6Al4V was evaluated through the reciprocating friction and wear test.The untextured WC-8Co was utilized as a control sample.The test results illustrated that the micro-groove on the WC-8Co was capable of anti-adhesion on the contact face,especially under high contact load.The anti-adhesion mechanism of the textured surface was resulted from the entrapment of debris by the microgroove.Moreover,unlike the untextured WC-8Co,the wear of the textured WC-8Co initially derived from the breakage of the micro-groove edge,and subsequently propagated to the friction surface.This wear behavior was attributed to the high thermal load and mechanical stress concentration on the micro-groove edge,as well as the synergistic effects of WC grain growth during laser machining and element diffusion in the sliding friction process.