Thermal desorption behavior of holmium and erbium hydride powders under vacuum heating

Abstract

The study investigates the thermal desorption behavior of holmium and erbium hydride powders during heating under vacuum to determine well-founded temperature–time parameters for the subsequent synthesis of lanthanide beryllides. The relevance of this study is determined by the need to account for gas evolution from hydride-containing powder mixtures during vacuum thermal treatment, since hydrogen desorption can significantly affect powder densification, vacuum stability, and phase formation conditions.

Before the thermal desorption (TDS) experiments, the initial powders of beryllium, holmium hydride, and erbium hydride were characterized, including analysis of particle size distribution, particle morphology, and phase composition. TDS studies were carried out under vacuum conditions with linear heating from room temperature to 1173 K at a rate of 10 K/min.

It is shown that heating of holmium and erbium hydride powders results in a multistage character with a dominant high-temperature peak.

The obtained results make it possible to determine the temperature ranges of the most intense gas evolution and can be used to justify vacuum heating regimes during the preparation and implementation of experiments on the synthesis of lanthanide beryllides from powder mixtures based on beryllium and rare-earth metals.