熔体旋淬Nb-Hf-Co渗氢膜的制备及其多气氛下的渗氢性能

Hydrogen is a promising clean energy. Hydrogen permeation (or hydrogen separation) is a key link in the process of hydrogen utilization and determines whether the hydrogen is in conformity with the standard of industrial application, which is highly concerned by the energy and material science. In this project, the material and technical objects are selected as Nb-Hf-Co alloy and melt spinning process, respectively. An optimum design of hydrogen permeable alloy composition is firstly put forward by thermodynamic calculation method. The location of the hydrogen permeable region in the phase diagram is specified. Then the hydrogen permeable alloy membranes are prepared by using melt spinning technique and the hydrogen permeability in multi-atmosphere is investigated. Also the intrinsic relationship between the alloy compositions, the technology parameters, microstructure and hydrogen permeability are revealed. In addition, the hydrogen permeation model is constructed and the hydrogen permeation mechanism is clarified. The technical conditions of melt spinning process with preparation of Nb-Hf-Co alloy are established, with the aim to produce a new type of hydrogen permeation membrane material with controllable thickness and excellent hydrogen permeability. On the one hand, the implementation of this project is to solve the problems about the blindness and complexity of component selection at the early stage of experiment for international scholars, supplementing and improving the phase diagram of this alloy. On the other hand, the problem of a low efficiency caused by the existing preparation process with a long time is also solved. Finally, it is hoped that the hydrogen permeable membranes of this alloy system can be used in the field from the laboratory research and development stage to the large-scale industrial production practice.

氢能是一种极具发展潜力的清洁能源。渗氢(或氢分离)是氢能利用过程中的关键环节，决定了获得的氢气是否符合工业化应用标准，正在受到能源及材料学科的高度关注。本项目以Nb-Hf-Co合金为材料对象，以熔体旋淬新工艺为技术对象，首先通过相图热力学计算方法对其渗氢成分进行优化设计，明确渗氢区域在相图中的位置；而后采用熔体旋淬技术制备渗氢合金(膜)，并研究其在多气氛下的渗氢性能，揭示合金成分、工艺、显微组织和渗氢性能之间的本征关系，构建氢渗透模型并阐明渗氢机制，确立采用熔体旋淬工艺制备该系渗氢膜的技术条件，由此获得膜厚度参数可控和渗氢能力优异的新型渗氢膜材料。本项目的实施一方面解决国际上众多学者在实验初期成分选择时的盲目性与复杂性等突出问题，补充并完善该系合金相图；另一方面解决该合金膜现有制备工艺耗时较长导致效率低下等问题，以期该系渗氢合金膜能够更好的从实验室研发阶段向大规模工业生产实践迈进。

氢能是一种极具发展潜力的清洁能源。渗氢(或氢分离)是氢能利用过程中的关键环节，决定了获得的氢气是否符合工业化应用标准，正在受到能源及材料学科的高度关注。本项目结合熔体旋淬工艺对含催化Pd膜层的Nb基氢分离合金膜（如：Nb-Hf-Co、Nb-Ti-Co和Nb-Zr-Co等）开展了一系列研究工作，并研究了上述合金膜在纯H2和混合气氛下的渗氢性能，项目实施过程中，确立了组织与参数控制的技术措施，由此为基础，成功获得了厚度约为60 μm、宽度为25 mm的非晶态薄膜，后期配合低温退火工艺显著提升了合金膜的渗氢流量和抗氢脆性能，首次发现了Nb基双相滤氢合金发生韧/脆性转化的临界区域，从根本上揭示了了Nb基双相合金优于单相合金的原因以及双相合金发生氢脆的原因，并提出了Nb基双相合金设计的新理念。本项目在国内外知名刊物发表论文18篇，其中SCI论文检索14篇(JCR一区：3篇；JCR二区：9篇；JCR三区：2篇)，另申请专利2项。这些科研成果不仅对于采用熔体旋淬技术制备高性能Nb 基氢分离合金(膜)的研究和实践提供技术支撑，而且对于丰富和发展多元合金相图理论也有重要的学术价值。