Al3Zr(p), Al2O3(p)/Al复合材料的反应机制
(1. 东南大学 机械工程系，南京 210096；
2. 江苏理工大学 材料科学与工程学院， 镇江 212013)
摘 要: 利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)，对ZrOCl2-Al体系熔体反应生成的复合材料组织进行了分析，结果表明： ZrOCl2-Al体系反应生成相为Al3Zr和α-Al2O3，颗粒尺寸为0.2～5 μm，形状以多面体为主；随反应起始温度升高，生成的颗粒体积分数增大，熔体温度也升高，但当熔体温度高于1 200 ℃时，Al3Zr出现聚集、长大。提出了ZrOCl2-Al体系的反应是气[CD*2]液反应和固液反应的复合过程，建立了ZrOCl2/Al反应中的控制环节ZrO2/Al反应的动力学模型及化学反应速率的关系式。
关键字: 反应机制； 复合材料； 熔体反应； ZrOCl2
Al2O3(p)/Al composites formed by reaction
between ZrOCl2 and liquid aluminum
（1. Department of Mechanical Engineering,
Southeast University, Nanjing 210096, P.R.China;
2. School of Material Science & Engineering,
Jiangsu University of Science and Technology，
Zhenjiang 212013, P.R.China）
Abstract:The microstructures of Al3Zr(p), Al2O3(p)/Al composites formed by reaction in melt from ZrOCl2-Al system were examined by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results indicated that Al3Zr andα-Al2O3 particulate phases are produced by the reaction between ZrOCl2 and liquid aluminum. The size of Al3Zr and Al2O3 particles with a polyhedral shape is in the range of 0.2～5 μm. The volume fraction of in-situ particles and the melt temperature are both enhanced with the increasing of initial reactive temperature. The ag.gregation and growth of Al3Zr particles occur when the melt temperature is higher than 1 200 ℃. It was proposed that the chemical reaction between zirconiu.m oxychloride (ZrOCl2) and liquid aluminum is a complex process including both. gas-liquid reaction and solid-liquid reaction. The kinetic model and the velo.city of chemical reaction for ZrO2/Al reaction, which is the key step in ZrOCl.2-Al reactive system, were established.
Key words: reactive mechanism; composites； reaction in melt； zirconium oxychloride
