【摘要】 研究了还原-扩散法合成LaNi₅、LaNi_4.5Mn_0.5和LaNi_4.5Cu_0.5金属间化合物的适宜条件,同时合成出La_0.5Ca_0.5Ni_4.5Mn_0.5金属间化合物。产物用X-射线粉末衍射进行了物相分析和化学分析测定了组成。以不同溶液冼涤合成产物时,发现LaNi₅、LaNi_4.5Mn_0.5、LaNi_4.5Cu_0.5的化学性质较稳定,用0.1MHCl洗涤后未见结构发生变化;而La_0.5Ca_0.5Ni_4.5Mn_0.5的化学性质较活泼,用0.1MHCl洗涤后结构发生变化。此外,从样品活化处理前、后X-射线衍射峰的宽度变化中发现,活化处理后晶粒在（110）晶面垂直方向的破碎度大于（101）晶面。更多还原

【Abstract】 The synthesises of LaNi_5-xM_x（M=Mn, Cu）and their properties have been studied. The optimum synthesising conditions for LaNi₅, LaNi_4·5, Mn_0·5, LaNi_4·5Cu_0·5 and La_0·5, Ca_0.5Ni_4·5Mn_0·5 have also been given in the paper. The X-ray diffraction results showed that all of these intermetallics were single phase and of hexagonal CaCu₅ structure. The lattice constants are:LaNi₅ a₀=5.027 c₀=3.987LaNi_4.5Mn_0.5 a₀ = 5.047 c₀ = 4.029LaNi_4.5Cu_0.5 a₀= 5.007 c₀=3.984La_0.5Ca_0.5Ni_4.5Mn_0.5 a₀=5.700 c₀=4.028LaNi₅synthesised by the method showing in this paper is more easily activated and has good performance in the absorption of hydrogen. LaNi₅-H system has a fairly flate plateau region, and maximum absorbed capacity can be expressed in formular LaNi₅H_5·76.The experimental results showed that, as the sample contained much calcium, the maximum absorbed capacity of hydrogen decreased obviously. The content of calcium was varied with different washing solvents; the sample washed by water contains much more calcim, and with those Washed by 0.1 M HC1 just a little calcium remains.LaNi₅, LaNi_4·5Mn_0·5 and LaNi_4·5Cu_0·5 are more stable than La_0·5Ca_0·5Ni_4·5Mn_0·5. When washing with 0.1 M HC1, the structure of the later ones changed obviously, but not the former ones.After activating treatment, LaNi₅ became fine powder. From the widened effect of the X-ray peaks, we found that the crystalline had been broken and the extent of the crush for（110）direction was larger（101）direction.更多还原