On the origin of the hydride precipitation-dissolution hysteresis in zirconium: Comments on Short Communication of G.A. McRae and C.E. Coleman published in Journal of Nuclear Materials 568 (2022) 153889

This is a comment paper on the work of McRae and Coleman recently published in Journal of Nuclear Materials 568 (2022) 153,889, where the diffusion of H atoms in to and away from “hydride-stabilising clouds” upon thermal cycling was deemed the sole origin of the precipitation-dissolution hysteresis. Here I explain why the nature of the transformation itself would lead to a thermal hysteresis, and discuss the possible reasons why the model of McRae and Coleman does not align with experimental results.