TiAl基合金与铸型的界面反应是控制铸件质量的关键因素，可影响合金的流动性和充型能力，也是杂质相的来源之一。但人们对该界面反应机制及产物控制等问题尚缺乏足够认识。申请人前期对二元TiAl合金液态置氢的研究发现，氢具有净化熔体、降低熔体粘度，提高流动性等作用，有望用于制备高纯复杂薄壁铸件。但目前仍没有该方面的研究报道，尤其是对于更具实用性的多元TiAl基合金。本项目拟将液态置氢拓展至多元TiAl基合金，主要研究液态置氢条件下合金与铸型的界面反应机制。首先研究氢对界面反应热力学、动力学、润湿性、反应产物的影响规律，获得合金与铸型界面反应机制的理论描述，进而利用氢对界面反应进行控制；同时探索界面反应与氢的耦合作用对铸造性能与微观组织演化的影响规律。本项目将揭示氢作用下TiAl基合金与铸型的界面反应机制，为控制界面反应过程和微观组织提供理论依据，具有较大的理论与实际意义。

The reaction between TiAl based alloy and casting mould is the key factor for the controlling of casting quality, because it can affect the flowability and mold-filling capacity and is one source of the impurity phases. However, the reaction mechanism and controlling of reaction products have not been realized sufficiently. The applicant studied the melt hydrogenation of binary TiAl alloy, and found that the hydrogen could purify the molten alloy, decrease the viscosity, and increase the flowability, so it is supposed to be used for increasing the filling capacity and purity of TiAl based alloys. But there are not relative research reports, especially for the practical multicomponent TiAl based alloys. This project is proposed to expand the melt hydrogenation to multicomponent TiAl based alloys. First, the effects of hydrogen on the interface reaction, including thermodynamics, reaction process, wettability and reaction products, will be explored for the further controlling of interface reaction by hydrogen. Then, the combined action of interface reaction and hydrogen on the casting property and solidification microstructure will be studied. This project will reveal the mechanism of interface reaction between TiAl based alloy and casting mould under the action of hydrogen, and will also provide theory support for the control of the process and products of interface reaction. So this project is significative for both theory and practical application.