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选用A356/SiC复合材料与Semi-metallic pad材料进行干滑动摩擦磨损试验,并采用SEM、XRD、EDS等手段分析了复合材料的摩擦磨损特点及磨损机制。铝基复合材料与该pad间表现出非常出色的耐摩擦磨损特性,在1m/s的低滑动速度下,即使载荷增加到700N也几乎不发生磨损;载荷不大于500N时,磨损率与滑动速度无关,保持非常小的范围。只有在高载荷、高滑动速度下才会有较为明显的磨损。摩擦系数则随载荷增大产生无规则变化,而随滑动速度的增加而减少,但变化幅度在0.1之内。复合材料耐磨特性好的主要原因是,磨损过程中磨损面上迅速形成以氧化物和石墨为主的润滑膜,减少磨损。高载荷、高滑动速度下磨损的主要特点为,复合材料表层形成塑性流动层,大的塑性流动变形使得较软的铝合金基体沿磨损方向以片状形式挤出,形成特殊的磨屑。而不易变形的SiC颗粒则留在磨损面上形成SiC聚集区,该区域又能在一定程度上减少进一步的磨损。
The dry sliding friction and wear tests of A356 / SiC composites and Semi-metallic pad materials were carried out. The friction and wear characteristics and wear mechanism of the composites were analyzed by SEM, XRD and EDS. The aluminum matrix composites showed excellent friction and wear resistance between the aluminum matrix composites and the pad. At low sliding velocity of 1m / s, there was almost no abrasion even when the load increased to 700N. When the load was less than 500N, the wear rate and sliding speed Has nothing to do, keep a very small range. Only in high load, high sliding speed will have more obvious wear and tear. The coefficient of friction then changes irregularly as the load increases, and decreases as the slip speed increases, but within a range of 0.1. The main reason that the wear resistance of the composite material is good is that the oxide film and the graphite-based lubricating film are rapidly formed on the wear surface during the wear process to reduce the wear. The main characteristic of wear under high load and high sliding speed is that the plastic material layer forms a plastic flow layer, and large plastic flow deformation causes the softer aluminum alloy matrix to be extruded in the form of sheet along the wear direction to form special wear debris. The SiC particles, which are not easily deformed, remain on the wear surface to form SiC agglomeration area, which can reduce further wear to a certain extent.