(1. 东北大学 材料与冶金学院, 沈阳 110004;
2. 抚顺铝厂, 抚顺 113001)
摘 要: 向铸铝ADC12熔体中添加硫酸铝铵， 由反应分解的Al2O3原位生成了颗粒增强铝基复合材料。 SEM观察表明， Al2O3颗粒在铝基体中细小弥散分布， 形成球形、 不团聚的增强体颗粒； Al2O3颗粒增强铝基复合材料中的片状共晶硅的数量比未增强合金的少， 且Al2O3邻近处的针状共晶硅非常精细。 与基材相比， Al2O3颗粒增强铝基复合材料的耐磨性较基材的提高了1~2倍， 硬度提高了15％， 且由硫酸铝铵反应自生成复合材料的耐磨性优于添加氧化铝形成的复合材料的。
关键字: 铝基复合材料； 氧化铝颗粒； NH4Al(SO4)2； 原位反应
（ 1. School of Materials and Metallurgy, Northeastern University,
Shenyang 110004, China;
2. Fushun Aluminium Co., Ltd, Fushun 113001, China）
Abstract: A new method was developed to fabricate in situ Al2O3 particles reinforced Al-based MMCs by adding NH4Al(SO4)2 into molten ADC12 aluminum alloy. The SEM results show that the in situ Al2O3 particles are generally spherical and they are distributed uniformly in the ADC12 matrix. In composites, the amount of flaky eutectic Si is lower than that in unreinforced Al-matrix, and in the vicinity of Al2O3, fiber eutectic Si is very fine. The wear test results show that the abrasive properties of composites increase remarkably, which are 1-2 times as high as that of the base metal and the hardness increases 15%, and the abrasive property of the in-situ composites is better than that of the composites by adding Al2O3.
Key words: Al-based metal matrix composites; alumina particle; NH4Al(SO4)2; in situ reaction
