【摘要】 为了提高La-Y-Mg-Ni合金的储氢性能，通过对铸态合金进行5～30 h的球磨，制备具有非晶和纳米晶结构的La_1.7Y_0.3Mg₁₆Ni合金，并研究显微组织对储氢性能的影响及其机理。结果表明，随着球磨时间的延长，合金的结晶度、晶粒尺寸和粒径减小，非晶相增加。纳米晶相和非晶相的双重调节作用导致储氢动力学性能先加快，后减慢。经过15 h球磨的合金具有最好的吸、放氢动力学特性，在373 K下10 min内可以吸收3.10%（质量分数）的氢气，其放氢活化能最低，为71.2 k J/mol。球磨不同时间的合金的热力学性能的变化很小，球磨15 h后合金的放氢焓变最低，为72.9 k J/mol。更多还原

【Abstract】 To improve the hydrogen storage property of La-Y-Mg-Ni alloy, the La_1.7Y_0.3Mg₁₆Ni alloys with an amorphous and nanocrystalline structure were prepared by ball milling the as-cast alloy for 5-30 h. The effects of microstructure on hydrogen storage property and its mechanism were analyzed. The results show that with prolonging milling time, the crystallinity, grain size and particle size decrease and the amorphous phases increase. The dual regulation of the nanocrystalline and amorphous phases results in the hydrogen storage kinetic property increasing at first and declining later. The 15 h-milled alloy gets the best hydrogenation and dehydrogenation kinetic property, which can absorb 3.10 wt.% hydrogen gas in 10 min at 373 K and has the lowest dehydrogenation activation energy of 71.2 kJ/mol. The thermodynamic property of the alloys milled for different time shows a little change, and the 15 h-milled alloy has the lowest dehydrogenation enthalpy change of 72.9 kJ/mol.更多还原