| 摘要 |
PROBLEM TO BE SOLVED: To provide a hydrogen storage alloy increased in hydrogen absorbing and releasing rates and showing excellent initial activation at the time of practical use. SOLUTION: This hydrogen storage alloy has an overall composition consisting of, by weight, 25-45% Zr, 1-12% Ti, 10-20% Mn, 2-12% V, 0.5-5% rare earth element composed essentially of La and/or Ce, 0.1-4% Hf, 0.01-0.2% hydrogen, and the balance Ni (contained by >=25%) with inevitable impurities. Moreover, this alloy has a structure in which hydrogen reaction product phases are dispersedly distributed in a matrix phase of Zr-Ni-Mn alloy and the main body of the hydrogen reaction product phases consists of (rare earth element)-Ni alloy and hydride of rare earth element and, further, numerous cracks generated at the time of formation of the hydrogen reaction product phases are present and the hydrogen reaction product phases are exposed to the internal surface of the cracks. |
