STUDY OF THE La-Ni-Ce TERNARY SYSTEM ACROSS THE LaNi5-CeNi5, LaNi5-CeNi, AND LaNi-CeNi POLYTHERMAL SECTIONS

Intermetallic compounds of transition metals, especially lanthanides, and the new phases based on them attract the attention of researchers as effective adsorbers for hydrogen. Using physicochemical analysis techniques, including Differential Thermal Analysis (DTA), Powder x-ray Diffraction (PXRD) and Scanning Electron Microscope (SEM), the ternary La-Ni-Ce system was investigated across the LaNi5-CeNi5, LaNi5-CeNi, and LaNi-CeNi polythermal quasi-binary sections. The corresponding (T-x) phase diagrams have been constructed for the title system. The phase diagrams are quasi-binary and of the eutectic type. The systems have revealed wide regions of solid solutions based on starting compounds LaNi5, LaNi, CeNi5, CeNi. It has been established that the coordinates of the eutectic point formed on the basis of the initial components for the LaNi5-CeNi5, LaNi5-CeNi, and LaNi-CeNi sections are 50 mol% CeNi5, 1150 °C, 68 mol% CeNi, 650 °C, and 50 mol% CeNi, 620 °C, respectively. The obtained variable-composition phases can be considered as promising materials for hydrogen absorption.