不同烧结工艺对贮氢合金LaMgNiCo的性能影响

借助XRD和SEM及EPMA研究La0.67Mg0.33Ni2.5Co0.5贮氢合金的烧结工艺对该合金的微观组织结构及电化学性能的影响。结果表明,在不同烧结条件下合金均由不含Mg的LaNi5相、富Mg的LaNi3相及一个贫Mg的LaNix（x=3.0-3.8）相三相组成。当烧结温度不超过1203k时合金主相为LaN i3相,当烧结温度超过1 203K,LaN i5相逐步成为主相。电化学性能分析结果表明,烧结温度不超过1203K,合金放电能力主要受合金组织形成与均匀性影响;而烧结温度超过1 203K,Mg元素挥发损失成为影响合金放电能力的决定因素。烧结条件为873k～1123k保持24 h、1203k保持2h,是制备La0.67Mg0.33Ni2.5Co0.5贮氢合金的适宜工艺。

Effect on Properties of Various Sintering Conditions of LaMgNiCo Hydrogen Storage Alloy

La0.67Mg0.33Ni2.5Co0.5 alloy were prepared by sintering with temperature stepwise way.From the XRD and SEM analyses,the micro-structural and electrochemical properties of the alloy has been studied systematically.It shows that the alloy is composed of the LaNi5 phase without Mg,the LaNi3 phase with abundance in Mg and a phase with shortage of Mg on various sintering conditions.The electrochemical properties show that discharge capacity of the alloy varies with structure,when sintering temperature is no high...