Formation of amorphous phase of R3In and R2In intermetallic compounds by hydrogenation

Phase transformation of R3In (R=La, Ce, Pr, Nd) and R2In compounds (R=La, Ce, Pr, Nd, Sm, Gd, Dy, Tb, Ho, Er) by hydrogenation were investigated by X-ray Diffractometry (XRD), Transmission Electron Microscopy (TEM) and Differential Scanning Calorimetry (DSC). Hydrogen-Induced Amorphization (HIA) has been observed in these compounds below 473 K. By hydrogenation at higher temperature, these compounds decompose into RH2 and RIn3. Hydride with the original crystal structure has not been obtained. The HIA behavior of R-In compounds and the crystallization behavior of the amorphized alloys are similar to those of R3Ga and R-Al compounds, and are different from those of the C15 Laves compounds RM2.