【摘要】 为了改善La-Mg-Ni-Al合金的循环稳定性,用Y部分替代合金中La元素,用真空感应熔炼与950℃完全退火处理制备了La_0.82-xY_xMg_0.18Ni_3.35Al_0.15（x=0⁰.45）合金。采用XRD分析了合金的相结构,并测试了其电化学性能,分析了Y含量对合金相结构及电化学性能的影响。结果表明,Y部分替代La后,合金相结构除了主相LaNi₅、（La,Y,Mg）₂（Ni,Al）₇外,还有Ni₃Y相,Y元素导致主相晶胞体积减小。与不含Y合金相比,含Y合金的电化学性能相对较好。合适的Y含量替代改善合金电极的电化学性能,在本实验研究范围内,Y含量为0.25时的合金具有相对较大的放电容量,Y含量为0.35时的合金具有相对较好的循环稳定性。更多还原

【Abstract】 In order to improve the cycling stability of La-Mg-Ni-Al alloy,the partial substitution of Y for La was performed,La_0.82-xY_xMg_0.18Ni_3.35Al_0.15（ x = 0- 0.45） alloys were fabricated by induction melting under vacuum and complete annealing at 950 ℃.Phase structure of the alloy was characterized by X-ray diffraction（ XRD）,the electrochemical performances of the alloys were measured and the effects of the replacement of La by Y on phase structure and electrochemical performances of the alloys were investigated.The results show that there is Ni₃Y phase after partial substitution of Y for La besides main phases including LaNi₅and（ La,Y,Mg）₂（ Ni,Al）₇phases,Y element induces the decrease of cell volume of the main phases.Comparing with free-Y alloy,the electrochemical performances of the alloys containing Y are better than those of the other.Suitable Y content can improve the electrochemical performances.In this experiment,discharge capacity of the alloy with Y content of 0.25 is higher than that of the other,however,the cycling stability of the alloy with Y content of 0.35 is better than that of the other.更多还原