Nb-Ti-Ni系氢分离合金冷坩埚定向凝固相选择特性与渗氢性能

项目名称： Nb-Ti-Ni系氢分离合金冷坩埚定向凝固相选择特性与渗氢性能

项目编号： No.51274077

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 矿业工程

项目作者： 李新中

作者单位： 哈尔滨工业大学

项目金额： 76万元

中文摘要： 采用自主开发的冷坩埚定向凝固技术研究Nb-Ti-Ni系氢分离合金相选择特性与渗氢性能，发挥其无熔体污染、较高温度梯度、适于制备大尺度试样的优势，解决长久以来采用整体凝固铸造方法制备该合金遇到的渗氢相晶粒随机分布导致渗氢性能低的突出问题。通过相图热力学计算，获得三元Nb-Ti-Ni合金中 "Nb-TiNi共晶沟"相平衡信息，揭示该合金冷坩埚定向凝固相选择特性，分析初生相与共晶相的竞争生长机制，并通过宏观物理场与微观共晶凝固模型相耦合，构建对流作用下定向凝固共晶合金相选择模型，同时揭示合金成分、凝固参数、凝固组织与渗氢性能之间的本征关系，阐明氢渗透机制，确立采用冷坩埚定向凝固技术制备具有高氢渗透度及抗氢脆性能的Nb-Ti-Ni系氢分离合金的技术条件。

中文关键词： 氢分离合金；氢传输；凝固路径；结构调控；

英文摘要： The self-invented cold-crucible directional solidification technology is used to investigate the phase selection characteristics and hydrogen permeability of Nb-Ti-Ni systems making use of its andvantages such as non-conamination of melt, high temperature gradient and ability of preparation of big-sized samples. The low hydrogen permeability of the present alloy is expected to be improved, which is prepared by the conventional free-solidification cast methods causing the random distribution of the hydrogen-permeable phase. Firstly, the equilibrium solidification information of L→Nb(Ti,Ni)+TiNi should be derived by Thermo-Calc of phase diagram. Secondly, The phase selection characteristics of Nb-Ti-Ni ternary eutectic under cold-crucible directional solidification will be investigated, as well as the competitive growth mechanism between primary and eutectic phases. And then, the phase selection model of directionally solidified eutectic alloys with effect of convection should be built by coupled calculations between macroscopic transimission model and microscopic eutectic growth model. Thirdly,the relationship among composition, solidification parameters, microstructure and hydrogen permeability will be characterized for Nb-Ti-Ni systems in cold-crucible directional solidification, and also the hydrogen permeable

英文关键词： Hydrogen permeable alloys;；hydrogen transportation；solidification path；structural modulation；