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运用等离子喷涂技术在7005铝合金表面制备了WC和CeO2颗粒协同增强镍基合金复合涂层,研究了该复合涂层的微观结构和摩擦学性能。结果表明:加入CeO2颗粒细化了复合涂层的显微组织,使WC增强颗粒从圆形变为不规则多边形,并降低了其脱碳分解程度。不同PV值摩擦条件下,WC-CeO2/镍基合金复合涂层的摩擦系数和磨损失重均低于WC/镍基合金复合涂层和镍基合金涂层。PV值小于3.36 N·m/s时,复合涂层磨损表面的最大接触应力低于其弹性极限接触应力,主要发生微观切削磨损和疲劳磨损;PV值大于3.36N·m/s后,磨损表面的最大接触应力超过其弹性极限接触应力,接触温度也急剧上升至648℃,磨损表面出现明显的塑性变形和脱落,其磨损机制变为多次塑变磨损、磨粒磨损和粘着磨损,并伴有氧化磨损。
The WC and CeO2 particles synergistically reinforced the Ni-based alloy composite coating on the surface of 7005 aluminum alloy by plasma spraying technology. The microstructure and tribological properties of the composite coating were studied. The results show that the addition of CeO2 particles refine the microstructure of the composite coating, make the WC reinforced particles change from circular to irregular polygon, and reduce the decarburization and decomposition degree. The friction coefficient and wear loss of WC-CeO2 / Ni-based alloy composite coatings were lower than those of WC / Ni-based alloy coatings and Ni-based alloy coatings under different PV values. When the PV value is less than 3.36 N · m / s, the maximum contact stress on the wear surface of the composite coating is lower than the elastic limit contact stress, and the micro-cutting wear and fatigue wear mainly occur. When the PV value is more than 3.36 N · m / s, Of the maximum contact stress exceeds its elastic limit contact stress, the contact temperature also rose sharply to 648 ℃, the wear surface obvious plastic deformation and loss, the wear mechanism becomes multiple plastic deformation wear, abrasive wear and adhesion wear, and with Oxidative wear.