(1. 東南大學(xué) 材料系， 南京 210096；
2. 南京理工大學(xué) 材料系， 南京 210094)
摘 要: 通過(guò)XD(Exothermic Dispersion)法原位反應(yīng)生成Al2O3與Al3Ti復(fù)合增強(qiáng)的鋁基復(fù)合材料，結(jié)果表明Al/TiO2經(jīng)充分混合、擠壓成坯后，在真空爐中以一定的升溫速率加熱至1 073 K左右時(shí)發(fā)生劇烈的化學(xué)反應(yīng)。由SEM，XRD及能譜分析可知：生成物Al2O3呈等軸顆粒狀，Al3Ti呈棒狀。主要分析了反應(yīng)過(guò)程的熱力學(xué)并簡(jiǎn)要說(shuō)明了影響XD合成的主要因素。
關(guān)鍵字:
exothemic dispersion synthesis technology
（1. Department of Materials Science and Engineering,
South East University, Nanjing 210096, P.R.China；
2. Department of Materials Science and Engineering,
Nanjing University of Science and Technology, Nanjing 210094, P.R.China）
Abstract:Al2O3 and Al3Ti reinforced aluminum matrix composites were prepared by means of exothermic dispersion (XD) in-situ synthesis technique. Its kinetic mechanism was also discussed. The results show that Al-TiO2 system can be reacted in very short time. The reaction is propagated in combustion wave. It is also shown that aluminum initially react with TiO2 to form Al2O3 and reduced Ti by X-ray diffraction and scanning electroric microscopy. Then the reaction between reduced Ti and aluminum is subsequently followed. The Al2O3 and Al3Ti take the shapes of equiaxed particle and block respectively. A certain heating rate and content of aluminum are needed，if thermal explosion occurs commonly in the Al-TiO2 system. The aluminum content and green density also have influences on the combustion temperature and bulk shrinkage. The combustion temperature would be lower for higher aluminum content, but its bulk shrinkage would be higher.
Key words: in-situ chemical reaction； thermodynamic； combustion wave； aluminum matrix composites
