冲击速度下的磨损行为
(广东工业大学材料科学与工程系, 广州510090)
摘 要: 为揭示MMCs材料的冲击磨损机理, 采用单摆划痕法对Al2O3f/Al-9Si合金耐冲击磨损行为进行了研究, 结果表明: (1) 在3m/s冲击速度下, 随着增强相的体积分数增多,Al2O3f/Al-9Si合金抗冲击磨损性降低。 在4m/s冲击速度下, 20% Al2O3f/Al-9Si合金具有最高的抗冲击磨损性,而25% Al2O3f/Al-9Si合金的抗冲击磨损性最弱。 对同一种Al2O3f/Al-9Si合金材料, 冲击速度为4 m/s时的耐冲击磨损性优于速度为3 m/s时的的耐冲击磨损性。 (2) 在冲击磨损过程中,Al2O3f/Al-9Si合金表面出现严重的犁沟和伴随发生的Al2O3短纤维被拉出基体形成空位的现象。
关键字: 冲击磨损;Al2O3f/Al-9Si合金; 速度效应; 划痕试验
(Department of Materials Science and Engineering, Guangdong University of Technology, Guangzhou 510090, P.R.China)
Abstract:The impact wear test by single pendulum scratch method is one of the methods for investigating the work and wear performance of the spares under dynamic moving conditions. The impact wear resistance of the Al2O3f /Al-9Si MMC was studied, the resistance to impact wear was found to depend on the impact speed significantly. At an impact speed of 3 m/s,it decreases with the increase of Al2O3f fiber volume fraction in the volume fraction range between 10 and 25 percent. The resistance at 4m/s impact speed maximized at the volume content of 20 percent, though it is higher than that at 3 m/s impact speed for all the studied Al2O3f content. SEM studies of the worn surface reveal two concurrent mechanisms, namely the serious plowing and the pull out of the Al2O3f short fibers.
Key words: impact wear; Al2O3f /Al-9Si MMC; speed effect; scratch tests