界面潤濕性的影響
(1. 哈爾濱工業(yè)大學(xué) 材料科學(xué)與工程學(xué)院， 哈爾濱 150001；
2. 復(fù)旦大學(xué) 材料科學(xué)系， 上海 200433)
摘 要: 采用液相包裹法對亞微米Al2O3顆粒表面進(jìn)行稀土氧化物Y2O3改性。 通過表面改性前后顆粒增強(qiáng)Al基復(fù)合材料制備過程中， Al熔體在顆粒間滲透壓力的變化， 研究了顆粒表面Y2O3改性前后與Al熔體間界面潤濕性的變化； 同時利用真空座滴法對界面潤濕性的變化進(jìn)行了評定。 結(jié)果表明： Al熔體在表面經(jīng)Y2O3改性的Al2O3顆粒中的滲透壓較改性前顯著降低； 顆粒表面改性后與Al熔滴間的接觸角明顯減少且與顆粒表面Y2O3包裹程度有關(guān)； 說明顆粒表面經(jīng)Y2O3改性后與Al基體間的潤濕性得到了明顯的改善， 且6061Al較2024Al對Al2O3顆粒具有更好的潤濕效果； 其改善的主要原因是Y2O3與基體Al發(fā)生了界面反應(yīng)， 體系產(chǎn)生了反應(yīng)潤濕的結(jié)果。
關(guān)鍵字: 亞微米Al2O3顆粒； 表面改性； 稀土； Al基復(fù)合材料； 界面潤濕性
（1. School of Materials Science and Engineering,
Harbin Instritute of Technology, Harbin 150001, China;
2. Department of Material Science, Fudan University,
Shanghai 200433, China）
Abstract: Liquid coated approach was used in rare-earth modification on the surface of sub-micron Al2O3 particles. The wetting behaviour of molten aluminum on the as-received and coated Al2O3 powders was investigated by the change of osmotic pressure between the molten aluminum and particles during the preparation of Al composites. At the same time, the change of the interfacial wettability was examined by the sessile drop method. The results show that the osmotic pressure between the melted aluminum and the Al2O3 particles coated by Y2O3 is obviously dropped. The contact angle of the coated-particles by Al decreases clearly and it is related to Y2O3 content on the surface of Al2O3 particles. The results show that the wettability of the coated-Al2O3 particles by liquid alumimum is dramatically improved, and the wetting effects of Al2O3 particles by 6061Al are better compared to 2024Al. The main reason for the improvement of the wettability can be suggested that it results from reaction wetting in the system due to the interface reaction of Y2O3 with Al matrix.
Key words: sub-micron Al2O3 particle; surface modification; rare-earth; aluminium matrix composite; interfacial wettability
