A reaction-diffusion analysis of the hydriding kinetics of zirconium-based alloys

One of the most critical points when studying hydriding kinetics of intermetallic compounds is to determine internal kinetic parameters (IKP) independent of sample geometry that allow to compare different systems. In this sense, theoretical modelling of the microscopic mechanisms taking place during the reaction is fundamental. In this work, we present a reaction-diffusion model for the hydrogen absorption in bulk Zry-4 samples. The model is based on two IKPs, easily measurable by simple experimental techniques: the hydrogen diffusion coefficient in the matrix and the reaction rate. Different relationships that arise from the model between measurable quantities (e.g. the hydride front velocity) and the IKPs are presented