Влияние гидрирования на структуру, магнитные и магнитокалоричеcкие свойства сплавов Tb-Dy-Co со структурой фаз Лавеса

A comprehensive study of the structure, phase composition, surface topology, magnetic and magnetocaloric properties of the compounds TbCo2, Tb0.3Dy0.7Co2 and the hydride with a low hydrogen content Tb0.3Dy0.7Co2H0.5 was carried out. The features of the structure at the micro- and nano- levels, as well as changes in the fundamental and functional properties during hydrogenation, were established. It was shown that the introduction of a small amount of hydrogen into the crystal lattice of the Tb0.3Dy0.7Co2 compound leads to an increase in both the Curie temperature and the magnetic moment on the cobalt atoms. The type of magnetic phase transition from a paramagnetic to a magnetically ordered state changes from the first (in the compound Tb0.3Dy0.7Co2) to the second (in TbCo2, Tb0.3Dy0.7Co2H0.5), which leads to a significant decrease in the magnitude of the magnetocaloric effect.