金属/陶瓷复合材料的原位合成及其结构研究

In-situ Preparation and Microstructure of Al(Si)/AlN/MgAl₂O₄ Composites

摘要: 以铝镁合金、高纯石英棒为原料,采用原位合成法在1473K氮气氛下保温2h制备了Al(Si)/AlN/MgAl2O4复合材料.采用XRD、SEM和EDX等方法分析了所得材料的相组成与显微结构.结果表明:复合材料的物相为MgAl2O4、Al-Si、AlN、Mg2Si和Si;在铝与SiO2界面上形成的Al2O3与基体合金中的镁反应生成块状的MgAl2O4尖晶石晶体,在复合材料内部发现均匀分布的AlN晶须,部分氧、铝、镁、铁形成化合物与硅一起均匀弥散分布于复合材料中.

Abstract: Al(Si)/AlN/MgAl2O4 composites were synthesized by the in-situ reaction from Al-Mg alloy and SiO2 for 2h at temperature of 1473K in nitrogen atmosphere.The products were characterized using microscopy,X-ray diffraction,scanning electron microscopy and energy dispersive X-ray analysis.The phase composition of the composites consisted of MgAl2O4,Al-Si,AlN,Mg2Si and Si.The microstructure of the composites showed that MgAl2O4 spinels were formed by Mg reacted with Al2O3 at the interface of Al/Al2O3.AlN crystal whisker was found in the composites.Some O,Al,Mg,Fe dissolved in the silicon alloy and homogeneously distributed in the composites around ceramic phases were found.