Multiple hydriding/dehydriding of Zr<inf>1.02</inf>Ni<inf>0.98</inf> alloy

Abstract

The hydriding kinetics and hydrogen absorption capacity of Zr1.02Ni0.98 alloy powder were investigated in a temperature range of 150-250 °C. An isothermal volumetric method within a pressure range of 0-1 bar was used. As expected, the temperature increase causes both an increase of the hydriding rate and a shift in the equilibrium of the Zr1.02Ni0.98+x/2H2↔Zr1.02Ni0.98Hx, reaction towards the left. Performing multiple hydriding/dehydriding cycles, an increase in hydriding rate accompanied by a decrease in maximal hydriding capacity was observed after each subsequent hydriding cycles of the same sample. Using X-ray diffractometry, this was shown to be a consequence of an irreversible destruction of the alloy.