Alloy design of cyclic hydro and dehydrogenation tolerant hydrogen storage materials

耐循环加氢和脱氢储氢材料的合金设计

基本信息

批准号：
11305048
负责人：
HANADA Shuji
金额：
$ 26.6万
依托单位：
TOHOKU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1999
资助国家：
日本
起止时间：
1999 至 2002
项目状态：
已结题

项目摘要

The objective of this study is to understand the effect of metallurgical factors on hydrogen absorbing properties and to indicate the appropriate alloys design of hydrogen storage materials with advanced cyclic properties. The results obtained are summarized as followsEffects of microstructure and composition on hydrogen absorbing properties in binary TiMn_2 based alloy: The hydrogen absorbing properties of binary TiMn_2 based alloys have been investigated as function of composition in the range between Ti-59.4 and -66.8 at.% Mn. The volume of fraction of TiMn_2 phase increases with increasing Mn content. The Mn content of TiMn_2 phase is almost constant atcompositions between Ti-56.4 and -59.4 at.% Mn, while is increases with increasing Mn content at compositions between Ti-59.4 nod -66.8 at.% Mn. Ti-59.4 at.% Mn containing TiMn_2 phase with 60 at.% Mn exhibits the superior hydrogen absorbing capacity and she least degradation of capacity during repeated hydrogen absorption and desorp … More tion. It is concluded that both hydrogen absorbing capacity and cyclic property in binary TiMn_2 based alloy are improved by increasing the volume fraction of TiMn_2 phase with keeping Mn content as low as possible.TiMn_2 based alloys: Degradation of the hydrogen absorbing capacity in cyclically hydrogenated TiMn_2 (Ti-60 at.% Mn) with Laves structure was studied by measurement of pressure-composition-isotherm (PCT) curves, X-ray diffraction and microstructure observation. Characteristic changes with cyclic hydrogenation are observed as follows. The hydrogen absorbing capacity remarkably decreases, the lattice constant increases, the amount of hydrogen retained in TiMn_2 increases and it approaches almost zero by dehydrogenation as 673 K in vacuum. Nano-sized regions with Mere patterns are produced in TiMn_2 with hydrogenation and Debye rings corresponding to titanium hydride δ-TiH appear in the diffraction pattern. Based on these observations it is concluded that the degradation of hydrogen absorbing capacity after cyclic hydrogenation is attributable to the introduction of retained hydrogen, heterogeneous strain and/or nano-regions. Less

本研究的目的是了解冶金因素对吸氢性能的影响，并指出具有先进循环性能的储氢材料的适当合金设计。所获得的结果总结如下：微观结构和成分对二元吸氢性能的影响。 TiMn_2 基合金：二元 TiMn_2 基合金的吸氢性能已被研究为 Ti-59.4 至 -66.8 at.% Mn 范围内成分的函数。 TiMn_2 相的分数随着 Mn 含量的增加而增加 TiMn_2 相的 Mn 含量在 Ti-56.4 和 -59.4 at.% Mn 之间几乎恒定，而在 Ti-59.4 和 -66.8 at.% Mn 之间则随着 Mn 含量的增加而增加。含有 60 at.% Mn 的 Ti-59.4 at.% Mn 相具有优异的吸氢性能结果表明，在保持 Mn 含量低的情况下，通过增加 TiMn_2 相的体积分数，可以提高二元 TiMn_2 基合金的吸氢能力和循环性能。 TiMn_2 基合金：通过测量 Laves 结构，研究了循环氢化 TiMn_2 (Ti-60 at.% Mn) 吸氢能力的降低通过压力-组成-等温线(PCT)曲线、X射线衍射和显微组织观察，观察到循环氢化后吸氢能力显着降低，晶格常数增加，TiMn_2中保留的氢量增加。通过脱氢，在真空中 673 K 下，TiMn_2 中产生具有 Mere 图案的纳米尺寸区域，并且氢化和德拜环对应于氢化钛。 δ-TiH 出现在衍射图中。基于这些观察，可以得出结论，循环氢化后吸氢能力的降低可归因于保留氢、异质应变和/或纳米区域的引入。