Mechanical activation: cold rolling, ball milling, and cold pressing

Mechanical activation refers to the use of processes like cold rolling, ball milling, and cold pressing to modify the microstructure and surface state of metal hydride alloys to improve their first hydrogenation behavior after air exposure.[1][2] In the Ti0.488Fe0.460Mn0.052 study, all three methods allowed hydrogen absorption by breaking passive oxide layers and introducing defects, with cold pressing delivering the highest hydrogen capacity and ball milling the fastest kinetics, while cold rolling offered effective regeneration with relatively simple processing.[1]