(1. 江苏科技大学 江苏省先进焊接技术重点实验室,镇江 212003;
2. Korea Institute of Machinery and Materials,Changwon 641—010,Korea)
摘 要: 以Al2O3陶瓷球为对偶材料,借助UMT-2摩擦磨损试验机详细研究温度变化对复合材料干滑动摩擦磨损特性的影响,并用SEM、EDS、奥林巴斯激光共焦扫描显微镜分析铸态SiCp/A356复合材料的高温摩擦磨损行为。结果表明:复合材料的磨损率对温度变化很敏感,在200 ℃以下,磨损率及其变化较小,以氧化磨损机制为主,属于轻微磨损;当温度达到250 ℃及以上时,磨损率开始急剧上升,磨损表面出现严重塑性流动痕迹,磨损面上出现磨屑粘着堆积的凸起,同时形成大量的大尺寸的磨屑,此时以粘着磨损机制为主,同时存在少量的氧化磨损。氧化磨损阶段,摩擦因数虽有变化,但相对稳定;但粘着磨损阶段,摩擦因数变得极度不稳定,出现尖锐的峰值。
关键字: SiCp/A356复合材料;制动盘;滑动摩擦;磨损
(1. Provincial Key Laboratory of Advanced Welding Technology,
Jiangsu University of Science and Technology, Zhenjiang, 212003, China;
2. Korea Institute of Machinery and Materials,Changwon 641-010, Korea)
Abstract:The influence of temperature change on the dry sliding friction and wear characteristics of as-cast SiCp/A356 composite was investigated on UMT-2 tribometer by using Al2O3 ceramic ball as dual material. The high temperature friction and wear behavior of the composite material were analyzed by SEM, EDS and Olympus confocal laser scanning microscope. The results show that the wear rate of the composites is very sensitive to the change of temperature. When temperature is less than 200 ℃, the wear rate and its change are relatively smaller. The wear mechanism is mainly oxidation wear, which is one form of mild wear. When the temperature reaches or is above 250 ℃, the wear rate increases quickly. And on the wear surface, there are severe plastic flowing wear traces, the bulge of stacked swarf adhesion and a large number of large sized wear debris. The wear mechanism mainly is adhesive wear and there is a small amount of oxidation wear as well. At oxidation wear stage, although the friction coefficient changes, but it is relatively stable. While at adhesion wear stage, the friction coefficient becomes extremely unstable, and a sharp peak appears.
Key words: SiCp/A356 composite; brake disc; sliding friction; wear