ELASTIC AND PLASTIC ACCOMMODATION EFFECTS ON HYSTERESIS DURING HYDRIDE FORMATION AND DECOMPOSITION

The elastic and plastic accommodation during hydride formation and decomposition and their effects on hysteresis are examined under the experimental conditions where there can be both pressure hysteresis and solvus hysteresis. It is shown that both the elastic and the plastic accommodation energies in both hydride formation and decomposition will contribute to hysteresis. The accommodation energies are generally not equal for hydride formation and hydride decomposition. The relative contributions of elastic or plastic energies to hysteresis are different for different types of materials. For practically important intermetallic compounds-hydrogen systems, elastic strain energy is the major cause of hysteresis. © 1990.