中文摘要：

采用电磁悬浮感应熔炼法制备La0.55Pr0.15Mg0.2Ni3.05Co0.35-x（AlFe）x（x=0.05,0.10,0.15,0.20,0.25）合金,并利用X 射线衍射（ XRD）、高倍率放电性能（ HRD）以及塔菲尔曲线（ Tafel）对合金相结构和电化学性能进行表征,研究Al和Fe替代Co对La Pr Mg Ni合金相结构以及电化学性能影响。结果表明,合金主要由LaNi5,Pr（ Ni,Co）5以及Pr2 MgNi9相组成。添加Al和Fe后,合金电极高倍率放电性能下降,随着Al和Fe替代Co含量的增加,La0.55Pr0.15Mg0.2Ni3.05Co0.35-x（AlFe）x（x=0.05,0.10,0.15,0.20,0.25）合金电极放电平台宽度依次减小。在合金电极表面形成的铝膜不利于氢原子的扩散,导致La0.55 Pr0.15 Mg0.2 Ni3.05 Co0.35-x（ AlFe） x （x=0.05,0.10,0.15,0.20,0.25）合金电极极限电流密度下降,但铝膜的抗腐蚀作用使合金电极容量保持率随着Al和Fe含量的增加逐渐增大。

英文摘要：

La0.55Pr0.15Mg0.2Ni3.05Co0.35-x（AlFe）x（x=0.05,0.10,0.15,0.20,0.25）alloys were pre-pared by magnetic levitation melting under argon atmosphere. The phase structure and electrochemi-cal performance of La0.55Pr0.15Mg0.2Ni3.05Co0.35-x（AlFe）x（x=0.05,0.10,0.15,0.20,0.25）alloys were investigated by means of X-ray diffraction （XRD）, high rate discharge ability （HRD） and Tafel testing. The results show that the samples mainly contain LaNi5, Pr（Ni,Co）5 and Pr2MgNi9 phases. The discharge platforms of La0.55 Pr0.15 Mg0.2 Ni3.05 Co0.35-x（AlFe）x（x=0.05,0.10,0.15, 0.20 ,0.25 ） alloy electrodes decrease with the Al and Fe content increasing. Because Al atoms form Al-coating on the surface of the electrodes, which impedes the hydrogen to diffuse, resulting in the decreasing of the limit current of the alloy electrodes. After adding Al and Fe elements, the dis-charge retention rate was improved due to the corrosion resistance of Al-coating.