Experimental investigation of hydrogen absorption by commercial high alloyed Ti2AlNb-based alloy in cast and rapidly solidified state

The possibility of hydrogenating a high alloyed intermetallic alloy based on Ti2AlNb compound with high hydrogen concentration at low pressure of about 0.1 MPa with hydride formation has been studied for the first time. The study is carried out using alloys fabricated by vacuum arc remelting (cast alloy) and pendent drop melt extraction (the rapidly solidified alloy). It is found that rapidly solidified alloy with 8-phase can absorb more than 2.0 wt % H. The high absorbing ability of the rapidly solidified alloy (fiber) is associated with a fine-dispersed microstructure and a high specific surface area. The cast alloy of a similar chemical composition with a coarsegrained microstructure and low specific surface area has low absorption ability in various phase compositions with maximum hydrogen absorption degree of 0.44 wt % H in quenched 8-phase state.