用ＤＴＡ对ＳｉＯ２ 与ＭｇＬｉ 合金反应合成复合材料的热力学进行了研究， 证明反应能够进行。检测结果表明反应生成的粒子尺寸细小且分布均匀。复合材料的强度、硬度、弹性模量明显提高； 该复合材料的延伸率低于基体合金， 但仍可达到较高水平（ ＞ ４％） ， 高于Ａｌ２Ｏ３ 及ＳｉＣ纤维增强复合材料。 The thermodynamics of composite materials synthesized by reaction of SiO2 and MgLi alloy was studied by DTA, which proved that the reaction can proceed. The test results show that the particles generated by the reaction are small and evenly distributed. The strength, hardness and elastic modulus of the composites increase obviously. The elongation of the composites is lower than that of the matrix alloy, but still reach a high level (> 4%) higher than that of Al2O3 and SiC fiber reinforced composites.