Microstructure and first hydrogenation properties of Ti30V60M10 + 4 wt% Zr (M=Fe, Co, and Ni)

The hydrogenation properties of Ti 30 V 60 M 10 (M = Fe, Co, and Ni) + 4 wt% Zr alloys at room temperature were investigated. The alloys were tested in their as-cast state and after being heat treated at 300 °C under a dynamic vacuum for 2 h. All as-cast alloys presented a two-phase microstructure consisting of a BCC matrix and a C14 secondary bright phase rich in Zr and M atoms. The BCC structure transformed into a face-centred cubic (FCC) main phase upon hydrogenation, while the C14 phase also hydrogenate but kept its structure. The as-cast alloys showed slow hydrogen absorption initially, but heat treatment reduced incubation times and improved hydrogenation kinetics for all compositions. • Investigated hydrogenation properties of Ti 30 V 60 M 10 (M = Fe, Co, and Ni) alloys with 4 wt% Zr at room temperature. • As-Cast alloys presented a two-phase microstructure of BCC matrix and C14 bright phase. • Heat treatment at 300 °C before activation reduced incubation times and improved hydrogenation kinetics. • Hydrogenation transformed the BCC structure to FCC, while the C14 phase also hydrogenate but kept its structure. • After heat treatment, Ti 30 V 60 Ni 10 alloy showed the most significant enhancement in hydrogenation kinetics.