抄録
Phases and thermal stability of new hydrides synthesized by using under a high pressure of 5 GPa in Ca–Mg–Ni–H systems were studied. The high-pressure synthesis was carried out at 1073 K–1223 K for 2 h under 5 GPa by using an anvil-type apparatus. A series of (Ca1−xMgx)2NiHδ was found to form solid solution in the range of x=0–0.4. This hydride decomposed around 646 K regardless of Mg content. In CaH2-X%MgH2 systems, hydrides with BCC structure were obtained in the range of X=50–67. Lattice constant of the BCC phase decreased from 0.4032(9) nm (X=50) to 0.3988(3) nm (X=67) with increasing Mg content. The decomposed temperature of the BCC phase increased from 650 K (X=50) to 673 K (X=67) with increasing Mg content, in other words, with decreasing the lattice constant of BCC phase.
