Hydrogen absorption in the Zr Al system

A series of ZrAl alloys has been prepared and the reaction with hydrogen studied by microbalance thermogravimetric analysis and differential thermal analysis. Their geometric and electronic structures have been studied by X-ray powder diffraction, X-ray photoelectron spectroscopy (XPS) and ion scattering spectroscopy (ISS). General tendencies related to increasing overall aluminium content in the alloys transcend any structural differences of different phases for the initiation of hydriding and for hydrogen solubility. The phenomena can be explained by the negative charge transfer from zirconium to aluminium resulting in a greater repulsion for hydrogen atoms by aluminium, and by the surface enrichment of zirconium though segregation observed in XPS and ISS analyses.