Influence of Laves phase on microstructure and hydrogen storage properties of Ti-Cr-V based alloy

Composites of Ti2CrV as the main matrix and ZrFe1.8V0.2 as the secondary matrix were prepared by two stage arc melting process and their microstructural characteristics as well as the hydrogen storage properties were investigated. X-ray diffraction (XRD) study reveals the presence of secondary phase. Electron Probe Micro Analysis (EPMA) illustrates that with increase in ZrFe1.8V0.2 concentration, the microstructure of the minor phase goes from dots to laminar to dendrites. With rise in the content of secondary phase in main Ti2CrV matrix, hydrogen absorption-desorption plateau pressures increases, and hydrogen storage capacity and plateau slope factor decreases. For all the cases the hydrogen absorption kinetics is found to be satisfactory. In-situ hydrogen desorption study shows that the stability of the hydrides decrease with increasing secondary phase concentration, which is important for practical application. Based on the hydrogen storage property analysis it has been concluded that Ti2CrV + 5% ZrFe1.8V0.2 composite exhibit the best overall performance for hydrogen storage application.