Influence of Ball Milling, Cold Rolling and Doping (Zr + 2Cr) on Microstructure, First Hydrogenation Properties and Anti-poisoning Ability of TiFe Alloy

In this paper, we found that the first hydrogenation properties of TiFe alloy can be significantly improved by ball milling, cold rolling and doping. The samples by ball milling for 60 min and doped with (Zr + 2Cr) as additive showed a faster hydrogenation kinetics and the sample cold rolled for 5 passes showed the highest hydrogen capacity. Further study, it was clear that the first hydrogenation of TiFe ingot could be easily activated by using ball milling. The first hydrogenation kinetics of ball-milled TiFe was strongly dependent on ball milling time. Doping (Zr + 2Cr) made TiFe alloy show excellent first hydrogenation kinetics and better anti-poisoning property due to the presence of bright phase. In addition, the doped sample with prolonged air-exposed time about 30 h could not be activated at all, but cold rolling could effectively make the totally dead sample active again and leads to the faster first hydrogenation kinetics and higher hydrogen storage capacity. Graphic Abstract