摘要
Ａｌ和Ｔｉ对Ｍｇ２Ｎｉ结构中部分Ｍｇ的取代，得到与Ｍｇ２Ｎｉ晶体结构不同的新型合金．多晶Ｘ射线结构分析表明，其化学式为Ｍｇ３ＭＮｉ２（Ｍ＝Ｔｉ，Ａｌ），立方晶系，空间群Ｆｄ３ｍ， Ｚ＝１６，４８个Ｍｇ坐落在４８（ｆ），１６个 Ｍ（Ｍ＝Ａｌ， Ｔｉ）坐落在１６（ｄ）位，３２个Ｎｉ坐落在３２（ｅ）位，Ｍｇ３ＡｌＮｉ２的晶胞参数ａ＝１．１５４７４（２）ｎｍ， Ｍｇ３ＴｉＮｉ２的ａ＝１．１６１７８（２）ｎｍ．与Ｍｇ２Ｎｉ相比，Ｍｇ３ＭＮｉ２合金的晶体密度更大，Ｍｇ－Ｎｉ键长更长，吸放氢温度降低，循环寿命延长．
A new phase different to Mg2Ni was obtained when Mg component in Mg2Ni was partially replaced by Al or Ti. X-ray powder diffraction structure analysis showed that the new phase is of cubic system, S. G. Fd3m, (No.227), the chemical formula Mg3MNi2 (M=Al, Ti). Z=16, sixteen molecules per unit cell, cell parameter a=1.15474(2) nm for Mg3AlNi2 and a=1.16178(2) nm for Mg3TiNi2, 48 atoms of Mg are located on 48(f) sites, 16 atoms of M (Ti, Al) on 16(d) and 32 atoms of Ni on 32(e). Compared with Mg2Ni, Mg3AlNi2 has bigger density and longer Mg-Ni bond length. Meanwhile, the hydriding/dehydriding temperature is lower and the electrochemical cycle life is longer.
出处
《金属学报》
SCIE
EI
CAS
CSCD
北大核心
2001年第5期459-462,共4页
Acta Metallurgica Sinica
基金
国家自然科学基金59671016
59781001
浙江省分析测试基金资助项目
