Ti和TiH_2与Al反应合成TiAl的研究

SYNTHESING TiAl ALLOY BY REACTION OF Ti AND TiH2 WITH Al POWDER

对采用ＤＳＣ、ＸＲＤ和ＳＥＭ３种方法分别由Ｔｉ和ＴｉＨ２粉末与Ａｌ粉末（５２％Ｔｉ和４８％Ａｌ）反应合成ＴｉＡｌ合金的过程及其机理进行了分析和探讨。Ｔｉ与Ａｌ，ＴｉＨ２与Ａｌ均需在Ａｌ转化为液态后才能进行剧烈的反应，但ＴｉＨ２与Ａｌ的反应是由ＴｉＨ２脱氢所产生的高活性Ｔｉ参与的，因而它们反应较完全，生成的ＴｉＡｌ相对量较高。随着反应的进行及Ａｌ元素的均匀化，反应初期生成的较不稳定的ＴｉＡｌ３相和αＴｉ相将消失。

The procedure of synthesing TiAl alloy by reaction of Ti and TiH2 powders with Al powder (52%Ti and 48%Al) was studied with DSC, XRD and SEM. Intense reactions of Ti with Al and TiH2 with Al would take place after Al element become melten. However, the reaction of TiH2 with Al is more complete, obtaining a higher amount of TiAl, because highly active Ti produced by decomposition of TiH2 participates in the reaction. With the development of the reaction and the homogenization of Al elements, less stable TiAl3 and αTi phases produced at the early stage of the reaction will disappear and the resultant from the reaction consists mainly of TiAl and less Ti3Al phases.