Crystal structure and phase abundance of Zr-Mn-Ni Laves phase hydrogen storage alloys

The crystal structure and phase abundance of Zr(Mn1-xNix)(2)(x=0.40 similar to 0.75) Laves phase hydrogen storage alloys were investigated by means of X-ray powder diffraction Rietveld method. It was found that Mn site of ZrMn2 alloy was partially substituted by Ni. The main phase structure of Zr-Mn-Ni alloy was of C15 type Laves phase. Ni element was considered to be a C15-stabilized element in ZrMn2 alloy. Over the studied composition range, the alloys were composed of Laves phases and some residual phases ZrMx. Laves phases including C15 and C14 type occurred over the studied composition range. The residual phases ZrM, Zr9M11 and Zr7M10 only appeared in a particular composition range. The lattice parameters and phase abundance of Laves phases changed with Ni concentration in alloys. The calculation of ANOE indicates that the occurrence of Laves phase in Zr(Mn1-xNix)(2) alloys is influenced by electron factors.