Hydrogen absorbing properties of a Ti–Zr–Mn eutectic alloy

Hydrogen storage properties of Ti-Zr-Mn eutectic alloys with the formula Ti 0.475 Zr 0.3 Mn0.225 were evaluated at ambient temperature and 565 °C using a Sieverts-type device. The initial alloys were stud ied by means of SEM-EDS technique, X-ray diffraction and DTA. The phase compositions and the crystal structures of the hydrogenation products were deter mined. The hydrogenation product obtained at room temperature consisted of an e e e e-hydride with a tetragonal crystal structure of ThH 2 type (a = 0.455 nm, c = 0.469 nm) and a Laves phase-based hydride with MgZn 2-type crystal structure (a = 0.5587 ±0.0005 nm, c = 0.9135 ±0.0007 nm) and had the composition 0.634(Ti 0.64 Zr 0.29 Mn 0.066 )H 1.96 + 0.366(Ti 0.18 Zr 0.32 Mn 0.5 )H 1.3 . The phase composition of the hydrogenation products obtained at 565 °C was estimated to 0.55(Ti 0.71 Zr 0.285 Mn 0.005 )H 1.85 + 0.45(Ti 0.19 Zr 0.32 Mn 0.5 )H 1.35 and consisted of a δ-hydride with a cubic crystal structure of CaF 2 type ( a = 0.4597 nm) and a Laves phase-based hydride with MgZn 2-type crystal structure ( a = 0.5598 ±0.0006 nm, c = 0.9192 ±0.0008 nm).