(四川大學 金屬材料系， 成都 610065)
摘 要: 討論了壁厚(1～10mm)對無釹低鈰低鈷LPC(NiCoMnAlCuFeSi)5和商用成分Mm(NiCoMnAl)5鑄態(tài)貯氫合金電化學性能的影響。 研究發(fā)現(xiàn)： 10mm厚的兩種合金活化性能均優(yōu)于1～6mm厚度合金； 在0.2C充放電制度下， 兩種合金的放電容量對鑄錠厚度均不敏感， LPC(NiCoMnAlCuFeSi)5合金的最大容量約為285mAh/g， Mm(NiCoMnAl)5合金的放電容量約為300mAh/g； 在1C充放電制度下， LPC(NiCoMnAlCuFeSi)5合金的最大容量約為250mAh/g， 對壁厚不敏感， Mm(NiCoMnAl)5合金的放電容量為250～280mAh/g， 對壁厚敏感， 并且前者顯示出更好的循環(huán)穩(wěn)定性。造成LPC(NiCoMnAlCuFeSi)5合金電化學性能對冷卻速度不敏感的主要原因是元素Cu、 Fe和Si的作用； 晶胞參數(shù)和內(nèi)應力等因素的交互作用也對該合金的性能有一定的影響。
關(guān)鍵字: 薄壁鑄造； AB5型貯氫合金； 鑄態(tài)； 電化學性能； 稀土
and Mm(NiCoMnAl)5 hydrogen storage alloys
LI Feng, TU Ming-jin, TANG Ding-xiang
（Department of Metal Materials,
Sichuan University, Chengdu 610065, China）
Abstract:The effect of thickness of as-cast ingots on the electrochemical properties of LPC(NiCoMnAlCuFeSi)5 and Mm(NiCoMnAl)5 hydrogen storage alloys was discussed. It is found that both alloys with 10mm thickness show better activation property than those with 1～6mm thickness. The maximum discharge capacity of both alloys at 0.2C is insensitive to the thickness of the ingots. The maximum discharge capacity of LPC(NiCoMnAlCuFeSi)5 is about 285mAh/g, and that of Mm(NiCoMnAl)5 is about 300mAh/g. The maximum discharge capacity of LPC(NiCoMnAlCuFeSi)5 alloy at 1C is around 250mAh/g and is insensitive to the thickness of ingots; and that of Mm(NiCoMnAl)5 alloy is 250～280mAh/g and is sensitive to the thickness. It is seen that the cyclic stability of the former is much better than that of the latter. The insensitivity of the electrochemical properties of LPC(NiCoMnAlCuFeSi)5 alloy to cooling rates is possibly due to the effect of Cu, Fe and Si. The interactions of crystal parameters and internal stress can also affect its properties to certain degrees.
Key words: strip casting; AB5-type hydrogen storage alloys; as-cast; electrochemical properties; rare earths
