Microstructure and First Hydrogenation Properties of Zr_1-xTi_xCr₂ Alloys Where x = 0, 0.25, 0.5, 0.75, and 1

Metal hydrides are an attractive way to store hydrogen in a compact and safe manner under low pressure. However, one of the hurdles to the widespread use of this method is the difficulty of the first hydrogenation, which increases the material cost. In this paper, we report the effect of substituting Zr with Ti in Zr_1-xTi_xCr₂ alloys (x = 0, 0.25, 0.5, 0.75, and 1) on the first hydrogenation. All the substituted alloys had similar microstructures and crystallized in the metastable C14 Laves phase. For x = 0, the first hydrogenation was possible at room temperature under 2 MPa of hydrogen pressure. As x increased, the hydrogen capacity decreased. For x = 0.75 and 1, first hydrogenation was practically impossible.