Emergence of hydrogen absorption ability in metastable HCP, FCC and amorphous Ti-Al alloys prepared by mechanical grinding

Abstract

Titanium aluminides [L10-TiAl (Ti0.50Al0.50 and Ti0.40Al0.60), TiAl2 and D022-TiAl3] have been mechanically ground (MG) in an argon atmosphere. In addition, hydrogen absorption and desorption properties of the MG-alloys have been investigated. Hcp- and amorphous (a-) TiAl, fcc- and a-TiAl2 and fcc-TiAl3 are formed by mechanical grinding (MG) of TiAl, TiAl2 and TiAl3, respectively. Although original Ti-aluminides do not absorb hydrogen, hcp- and a-TiAl, and fcc- and a-TiAl2, prepared by MG, having a fresh surface absorb hydrogen of the amount of 0.4 - 0.1 (H/M). The present work clearly demonstrates that MG is a useful technique for an emergence of the hydrogen absorption ability of intermetallic compounds containing much hydride-forming elements.