Influence of metal powder particle's shape on the kinetics of hydriding

The aim of this paper is to study the influence of the metal powder particle's shape on the kinetics of isothermal hydriding under constant pressure. We present arguments that this influence is small and may be neglected. The mathematical model of hydriding is described and applied to two series of experimental curves (for uranium and magnesium) for three convenient symmetrical model shapes: sphere, long thin cylinder, and flat thin plate. The fitting shows that quality of the approximation of the experimental curves by the model ones is comparable for these three shapes (yet spheres and cylinders provide better results compared to a plate) for similar kinetic parameters. The reasons for the shape-independent behaviour are discussed using some theoretical arguments based on the suggested model.