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采用端部淬火熄灭法分析了蔓延式燃烧合成Ｔｉ－５０ａｔ％Ａｌ合金中的组织结构转变动力学过程，发现合成反应从铝粉熔化处开始，合成反应表现为Ｔｉ＋Ａｌ→１／３ＴｉＡｌ３＋２／３Ｔｉ→ＴｉｘＡｌ＋（１－ｘ）Ｔｉ→ＴｉＡｌ等一系列过渡反应过程，这些反应的前期是可依靠液态反应物流动铺展进行质量传递的快速液－固型反应，可使试样温度迅速升高，为后续固－固型反应奠定良好扩散条件．由于扩散质量传递速度明显低于液相流动铺展，合成后期固－固反应速度较慢，在较快降温等条件下合成反应不能彻底完成，合金中将残留一部分未反应Ｔｉ芯，在反应后的冷却中，这些Ｔｉ芯表层含铝量较高部分可转化为α２－Ｔｉ３Ａｌ相，形成在Ｔｉ芯和ＴｉＡｌ产物间分布环状α２－Ｔｉ３Ａｌ相的特有组织结构．
The end-quenching quenching method was used to analyze the structural dynamics of Ti-50at% Al alloy. The results show that the synthesis reaction starts from the melting point of aluminum powder and the synthesis reaction is Ti + Al → 1 / 3TiAl3 + 2 / 3Ti → TixAl + (1-x) Ti → TiAl and so on. The early stage of these reactions is a rapid liquid-solid reaction which relies on liquid reactant flow spreading for mass transfer, and the sample temperature can rapidly increase for the subsequent solidification - solid reaction to establish a good diffusion conditions. Since the diffusion rate of mass transfer is much lower than that of liquid flow, the solid-solid reaction rate is slow at the late stage of synthesis, and the synthesis reaction can not be completely completed under the conditions of rapid cooling. Some unreacted Ti core will remain in the alloy after the reaction During cooling, the higher aluminum content of these Ti core layers can be transformed into α2-Ti3Al phase, forming a unique microstructure of the cyclic α2-Ti3Al phase distributed between the Ti core and the TiAl product.