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通过热力学计算，选择Ｎｉ_２Ｏ_３粉末作原材料，采用反应挤压铸造方法实现了Ａｌ与Ｎｉ２Ｏ３直接压铸反应合成Ａｌ３Ｎｉ－Ａｌ２Ｏ３－Ａｌ原位复合材料。研究了压铸工艺参数和预制块中纯Ａｌ粉的含量对反应合成复合材料过程的影响，并对反应机理做了较深入的分析。结果表明，Ｎｉ２Ｏ３与Ａｌ的反应是为高放热反应，反应是爆发式的，通过调整预制块中Ａｌ粉的体积分数控制了反应的剧烈程度，并能获得不同组成和基体含量的复合材料。对反应机理的分析表明，在Ａｌ足量的情况下，Ｎｉ２Ｏ３与Ａｌ反应合成复合材料分为两个过程，一是反应过程，即Ｎｉ２Ｏ３＋Ａｌ→Ａｌ２Ｏ３＋［Ｎｉ］；二是凝固过程，即反应后多余的Ａｌ与反应生成的［Ｎｉ］在随后冷却中的凝固过程，最终形成Ａｌ３Ｎｉ＋α－Ａｌ２Ｏ３＋Ａｌ复合材料。
Through the thermodynamic calculation, Ni_2O_3 powder was selected as the raw material and Al3Ni-Al2O3-Al in-situ composites were prepared by direct compression casting of Al and Ni2O3 by reaction extrusion casting. The influence of the die-casting process parameters and the content of pure Al powder in the pre-block on the reaction synthesis of composite materials was studied. The reaction mechanism was further analyzed. The results show that the reaction between Ni2O3 and Al is highly exothermic and the reaction is explosive. The intensity of the reaction can be controlled by adjusting the volume fraction of Al powder in the preform, and the composites with different compositions and matrix contents can be obtained. The analysis of the reaction mechanism shows that in the case of sufficient amount of Al, Ni2O3 reacts with Al to synthesize the composite material into two processes, one is the reaction process, namely Ni2O3 + Al → Al2O3 + [Ni]; the second is the solidification process, that is, Of Al and the reaction of [Ni] in the subsequent cooling of the solidification process, the final formation of Al3Ni + α-Al2O3 + Al composite material.