Cycle Stabilities of La0.7 Mg0.3 Ni2.55-x Co0.45 Mx (M=Fe, Cu, Al;x=O, 0.1)Electrode Alloys Prepared by Casting and Rapid Quenching
La-Mg-Ni system (PuNi<,3>-type) hydrogen storage alloys La<,0.7> Mg<,0.3> Ni<,2.55-x> Co<0.45> Mx (M=Fe, Cu, Al;x=0, 0.1) were prepared by casting and rapid quenching. Aiming to improve the cycle stabilities of the alloys, Ni in the alloy was partly substituted by Fe, Cu and Al. The effects of the substitution of Fe, Cu and Al for Ni and the rapid quenching on the microstructures and electrochemical properties of the alloys were investigated in detail. The results obtained by XRD, SEM and TEM indicate that the element substitution has no influence on the phase compositions of the alloys, but it changes the phase abundances of the alloys. Particularly, the substitution of Al and Cu obviously increases the amount of the LaNi<,2> phase. The substitution of Al and Fe leads to a great refinement of the as-quenched alloys grains. The substitution of Al strongly restrains the formation of the amorphous in the as- quenched alloy, but the substitution of Fe and Cu is quite helpful for the formation of an amorphous pase. The effects of the substitution of Fe, Cu and Al on the cycle stabilities of the as-cast and quenched alloys are different. The positive impact of the substitution elements on the cycle stabilities of the as-cast alloys is ranked in proper order Al>Fe>Cu, and for as-quenched alloys, the order is Fe>Al>Cu. Rapid quenching engenders an unconscious influence on the phase composition, but it markedly enhances the cycle stabilities of the alloys.
La-Mg-Ni system electrode alloy element substitution rapid quenching microstruetures cycle stability rare earths
Zhang Yanghuan (张羊换) Zhao Dongliang (赵栋梁) Dong Xiaoping (董小平) Guo Shihai (郭石海) Qi Yan (祁焱) Wang Xinlin (王新林)
Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 10008 Department of Functional Material Research, Central Iron and Steel Research Institute, Beijing 10008 School of Materials, University of Science and Technology Beijing, Beijing 100083, China
国际会议
第五届国际稀土开发与应用研讨会(The Fifth International Conference on Rare Earth Decelopment and Applicatin)
包头
英文
419-425
2007-08-07（万方平台首次上网日期，不代表论文的发表时间）