Absorption and desorption of hydrogen from zirconium foil

Abstract

Over a limited range of temperature (400–750°C) zirconium metal both absorbs and emits hydrogen as a function of the hydrogen pressure. The rates of the two processes have been measured and the activation energies associated with dissolution of hydrogen and the formation and decomposition of zirconium hydride have been inferred. The difference between the activation energy for dissolution and that for emission from solution gives a value of 52.5 kJ/g-atom which corresponds closely to the heat of solution of hydrogen in α-zirconium. The rate-controlling step for hydrogen emission is the loss from solution and not hydride decomposition.