沖擊速度下的磨損行為
(廣東工業(yè)大學材料科學與工程系, 廣州510090)
摘 要: 為揭示MMCs材料的沖擊磨損機理， 采用單擺劃痕法對Al2O3f/Al-9Si合金耐沖擊磨損行為進行了研究， 結果表明: (1) 在3m/s沖擊速度下， 隨著增強相的體積分數(shù)增多，Al2O3f/Al-9Si合金抗沖擊磨損性降低。 在4m/s沖擊速度下， 20% Al2O3f/Al-9Si合金具有最高的抗沖擊磨損性，而25% Al2O3f/Al-9Si合金的抗沖擊磨損性最弱。 對同一種Al2O3f/Al-9Si合金材料， 沖擊速度為4 m/s時的耐沖擊磨損性優(yōu)于速度為3 m/s時的的耐沖擊磨損性。 (2) 在沖擊磨損過程中，Al2O3f/Al-9Si合金表面出現(xiàn)嚴重的犁溝和伴隨發(fā)生的Al2O3短纖維被拉出基體形成空位的現(xiàn)象。
關鍵字: 沖擊磨損；Al2O3f/Al-9Si合金； 速度效應； 劃痕試驗
（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
