METHOD FOR IMPROVING PROPERTIES OF METALLIC MATERIAL FOR HYDROGEN STORAGE

摘要

PURPOSE:To increase the amt. of hydrogen to be occluded in the metallic material for hydrogen storage, to facilitate its activating operation and to improve its plateau properties by subjecting an alloy having specified compsn. constituted of Fe, Ti, rare earth elements and Co to heat treatment at prescribed temp. in the atmosphere such as vacuum. CONSTITUTION:An alloy having the compsn. shown by Fe1-xTiyREMzCOx (where REM denotes rare earth elements and, by the ratio of atomic number, (X) denotes 0.01 to 0.2, (y) denotes 0.9 to 1.05 and (z) denotes 0.015 to 0.1) is refined. The alloy is subjected to heat treatment at 900 to 1100 deg.C in vacuum or in the atmosphere of inert gas. Thus, the plateau properties defined by dln(Pd)/d(H/M) (where Pd denotes dissociation pressure of hydrogen in the part showing plateau, (H/M) denotes the amt. of hydrogen to be occluded, H denotes the number of hydrogen atoms and M denotes the number of alloy atoms) can be improved.