碳纤维切向微动磨损特性研究

在自制的多功能微动腐蚀试验机上，通过改变法向载荷和位移幅值，以碳纤维为研究对象开展球-面接触模式下的微动磨损试验. 建立了微动运行工况图、F_t-D曲线和摩擦系数曲线，探究了碳纤维的微动磨损运行特性；结合光镜(OM)、扫描电镜(SEM)、白光干涉仪和X射线光电子能谱(XPS)对磨损形貌及磨屑成分进行了分析，探究了碳纤维的微动磨损机理. 结果表明:随法向载荷的减小、位移幅值的增加，微动磨损区域由部分滑移区、混合区向滑移区转变. 摩擦系数随法向载荷的增加而减少，随位移幅值的增加而增加. 磨损体积随法向载荷和位移幅值的增加而增加；在部分滑移区和混合区，磨损率随载荷的增加而减小，在滑移区，磨损率存在波动，但依旧呈上升趋势. 混合区和滑移区的磨损机理为磨粒磨损、剥层和氧化磨损，但混合区氧化磨损较为严重. 位移幅值和法向载荷对碳纤维微动磨损行为影响较大，对摩擦系数以及磨损体积也有较为显著的影响. 混合区和滑移区微动磨损机理主要表现为磨粒磨损、剥层和氧化磨损. 

Fretting Wear Damage Characteristics of Carbon Fiber

The fretting of carbon fiber was produced on the self-made multi-function fretting corrosion tester, by changing the normal load and the displacement amplitude. The running condition fretting map, F_t-D curve and friction coefficient curve were established. The fretting wear operation characteristics of carbon fiber were explored; combined with optical microscope, scanning electron microscope, white light interferometer and X-ray photoelectron spectroscopy. The fretting wear mechanism of carbon fiber was explored by the investigating wear morphology and wear components. The results show the transition of fretting wear regime from partial slip regime or mixed regime to slip regime was observed by decreasing normal load and increasing displacement amplitude. Increasing normal load and decreasing displacement amplitude decreased the friction coefficient. Wear volume increased with increasing normal load and displacement amplitude. In the partial slip regime and the mixed regime, the wear rate decreased with the increase of the normal load. In the slip regime, the wear rate fluctuated and increased with normal load. The wear mechanisms of the mixed regime and the slip regime were abrasive wear, delamination and oxidative wear, while the oxidation wear in the mixed regime was more severe. The displacement amplitude and normal load had a great influence on the fretting wear of carbon fiber, friction coefficient and wear volume. The fretting wear mechanisms of the mixed regime and the slip regime were mainly represented by abrasive wear, delamination and oxidative wear.