When hydrogen is dissolved in palladium, the α phase forms first; the β phase nucleates and
grows in this. Because of the large volume change which accompanies the α‐to‐β transition,
plastic deformation of the α phase occurs as it is stretched beyond its elastic limit. Hence,
absorption is accompanied by growth of the β phase under compressive stress of the α
phase, but desorption take place from the β phase of the plastically deformed solid. Since
this is not a thermodynamically reversible process, hysteresis results. It is shown that the …