Magnetic properties of the YCo3–H system

Abstract

The YCo3–H system is an interesting system, which shows a dramatic influence of hydrogen absorption on its magnetic properties. The β-hydride phase has been divided into β1 and β2 phases originally due to their different magnetic properties. Our measurement of the absorption isotherm at room temperature, however, shows clearly that the β phase is actually separated into two phases. Thus a new hydride phase has been identified. Magnetisation measurements have also been made using a VSM. The results show that the β1 phase is most likely to be paramagnetic. We also observe that the β2 phase seems to have two Curie temperatures. Because there are three types of Co atoms in the YCo3 structure, we would infer that the magnetic ordering of the different Co atoms takes place at different temperatures in this phase.