Methods to Improve the First Hydrogenation of the Vanadium-Rich BCC Alloy Ti16V60Cr24

In this paper we report the effect of three different preparation methods on first hydrogenation vanadium-rich BCC alloy Ti16V60Cr24: one-time cold rolling, 5 min ball milling and addition 4 wt.% Zr. All samples were synthesized by arc melting. Without Zr was single phase, but when added, a secondary zirconium-rich phase present. However, X-ray diffraction patterns only showed single-body-centred cubic before for all samples. The crystal structure fully hydrogenated body-centred tetragonal. highest hydrogen capacity (3.8 wt.%) measured Zr-doped alloy. ball-milled also exhibited high storage fast kinetics. maximum slightly decreased after rolling. It found that air exposure increases incubation time hydrogenation. shortened rolling which, however, reduced capacity. Pressure-Composition isotherms Ti16V60Cr24 + at 297, 303 323 K determined. determined enthalpy entropy hydrides formation −41 ± kJ/mol −134 14 J/mol/K, respectively.