Al-Ti-C 系中反应生成 TiC 机理研究

Formation Mechanism of TiC in Al-Ti-C System

采用激冷实验，ＳＥＭ和ＸＲＤ对反应合成法制备Ａｌ／ＴｉＣ复合材料中ＴｉＣ反应生成机理进行了研究。结果表明，反应机理是一种溶解－析出过程，其间钛溶解于熔化了的铝液中并扩散到碳颗粒周围形成富钛层，富钛层中的钛与碳发生反应生成ＴｉＣ并从铝液中析出。同时也表明，反应生成ＴｉＣ的过程可以分为三个阶段：预制块中铝粉的熔化；Ａｌ３Ｔｉ相的形成和分解；ＴｉＣ颗粒的形成。最后，建立了反应生成ＴｉＣ的理论模型。

The mechanism of reaction synthesis TiC in Al/TiC composites prepared by direct reaction synthesis (DRS)has been investigated in detail by use of quenching experiment, XRD and SEMThe results have shown that the reaction mechanism is a solutionprecipitation mechanism, in which titanium dissolves into melted aluminium and reacts with carbon atom at the surface of carbon to form TiC, and then TiC particle precipitates out of the melt It has also been shown that the processing of reaction synthesis TiC can be devided into three stages:melting of aluminium powder in the preform, formation and resolution of Al3Ti phase in the melted aluminium and the synthesis of TiC particles In the end, a mechanism model of DRS to prepare Al/TiC has been established