熔盐保护熔炼法制备La2Mg17合金及其储氢性能

Hydrogen Storage Properties of La_2Mg_(17) Alloy Prepared by a Smelting Method with Protection by Molten Salt

采用熔盐保护熔炼法（SMPMS）成功制备了La2Mg17储氢合金。SEM和EDS研究发现，熔炼时液相在凝固过程中形成微观成分不均匀的非平衡组织。通过PCT性能测试发现，合金在523-623K时可逆吸放氢量大于4．3％（质量分数，下同）。动力学分析结果表明，合金在473～623K时具备良好的氢化动力学性能，并且在523K时出现氢化速率极大值（25s内吸氢3．2％）。丰富的表面裂纹改善了合金的储放氢性能。

The La2Mg17 hydrogen storage alloy was prepared by a smelting method with protection by molten salt （SMPMS）. During solidification process, the non-equilibrium, non-uniform microstructures were formed and observed through SEM and EDS. The study on the pressure-composition isotherm and kinetics of hydrogen adsorption shows that the reversible hydriding amount in the alloy is more than 4.3% （mass fraction） in the temperature range of 523-623 K. Good absorption kinetics of the alloy was found at 473-623 K. The optimal hydriding rate appeared at 523 K, and the alloy can absorb 3.2% （mass fraction） hydrogen within 25 s. The great amount of the surface cracks improved the hydrogen storage property of the alloy The factors on the improvement in hydriding kinetics were also discussed.