【摘要】 采用粉末冶金加压烧结技术制备含单斜和立方2种晶型ZrO₂的铜基摩擦材料,研究在干摩擦及不同制动速度条件下,ZrO₂晶型对铜基粉末冶金摩擦材料摩擦学性能的影响;用光学表面分析仪和扫描电子显微镜分别对试样磨损表面形貌及磨屑形貌进行观察,探究ZrO₂晶型对粉末冶金摩擦材料摩擦学性能的作用机制。结果表明:在相同条件下,含单斜相ZrO₂摩擦材料的摩擦因数及磨损量均高于含立方相ZrO₂的摩擦材料;随着制动速度的升高,2种材料的摩擦因数均降低,而含立方相ZrO₂材料摩擦因数降幅较小,同时两者的磨损量均呈现先上升后降低的趋势。随制动速度提升,含单斜相ZrO₂的摩擦材料主要磨损机制由黏着磨损与犁削磨损转变为剥层磨损;而含立方相ZrO₂的摩擦材料主要磨损机制由犁削磨损转变为犁削磨损与氧化磨损,最后转变为剥层磨损。更多还原

【Abstract】 Copper-based friction materials containing ZrO₂ in different crystal structures were prepared by powder metallurgy（P/M） pressure sintering technology,and the effect of crystal structures of ZrO₂ on tribological properties of copperbased P/M friction materials at different braking speeds was investigated under dry conditions.The wear surface morphology and the debris morphology of the samples were respectively observed by optical surface analyzer and scanning electron microscopy,and the effect mechanism of the structures of ZrO₂ on the tribological properties of powder metallurgy friction materials was explored.The results show that the friction coefficient and wear rate of the friction material containing monoclinic ZrO₂ are higher than those of the friction material containing cubic ZrO₂ under the same conditions.With increasing the braking speed,the friction material with cubic ZrO₂ suffers relatively smaller decline in the friction coefficient in comparison to the friction material with monoclinic ZrO₂,the wear rate of both materials is increased firstly and then decreased.With increasing the braking speed,the wear mechanism of the friction material containing monoclinic ZrO₂ is changed from adhesive wear and plough wear to delamination wear,while the wear mechanism of the friction material containing cubic ZrO₂ is transformed from plough wear to oxidation wear and to delamination wear finally.更多还原