中文摘要：

应用铸造及快淬工艺制备了La0.7Mg0.3 Co0.45Ni2.55-xCux（x=0，0．1，0．2，0．3，0．4）贮氢电极合金，研究了快淬工艺对合金微观结构及电化学性能的影响。XRD，SEM及TEM的分析结果表明，铸态及快淬态合金具有多相结构，包括（La，Mg）Ni3相，LaNi5相以及LaNi2相。快淬对合金的相组成没有明显影响，但显著地改变了合金的相丰度。快淬还显著地改善合金的成分均匀性，并使合金的晶粒明显细化。电化学测试的结果表明，快淬大幅度提高合金的电化学循环稳定性，但使合金的放电容量和活化性能下降。快淬对合金的放电电压特性具有明显的影响，当淬速大于15m／s时，快淬降低合金的放电电压，并使放电平台的斜率明显增大。

英文摘要：

The hydrogen storage alloys La0.7Mg0.3 Co0.45Ni2.55-xCux （x = 0, 0.1, 0.2, 0.3, 0.4） were prepared by casting and rapid quenching. The effects of the rapid quenching on the microstructures and electrochemical performances of the specimen alloys were investigated in detail. The results obtained by XRD, SEM and TEM show that the as-cast and quenched alloys have a multiphase structure, including the （La, Mg）Ni3 phase, the LaNi5 phase and the LaNi2 phase. The rapid quenching has no much influence on the phase compositions of the alloys, but it obviously changed the phase abundances of the alloys. The rapid quenching can significantly improve the composition homogeneity of the alloys and markedly decrease the grain size of the alloys. The results obtained by the electrochemical measurement indicate that the rapid quenching obviously enhances the cycle stability of the alloys, but it decreases the discharge capacity and the activation capability of the alloys. The rapid quenching had an obvious influence on the discharge potential of the alloys. When the quenching rate was larger than 15 m/s, it clearly decreased the discharge plateau potential and increased the slopes of the discharge potential plateaus of the alloys.