Hydrogen absorbing alloys and process for producing same

摘要

A hydrogen absorbing alloy is provided which is increased in reaction rate without being restricted in composition and which is unimpaired in the reversibility of reaction and hydrogen absorption-desorption cycle life characteristics. The alloy contains the phase of an intermetallic compound of the composition A5T19 wherein A is at least one element selected from the group consisting of La, Ce, Pr, Sm, Nd, Mm (misch metal), Y, Gd, Ca, Mg, Ti, Zr and Hf, and T is at least one element selected from the group consisting of B, Bi, Al, Si, Cr, V, Mn, Fe, Co, Ni, Cu, Zn, Sn and Sb. The alloy is produced by mixing together an alloy containing an AT3 phase and an alloy containing an AT4 phase, mechanically alloying the mixture to form the phase of intermetallic compound of the composition A5T19 in addition to the AT3 and AT4 phases, and subsequently mixing together or mechanically alloying the resulting alloy and an alloy containing AT5 phase.