Hydrogen-Induced Amorphization in C15 Laves Phase DyCo2 Studied by Pressure Calorimetry
Structural changes in C15 Laves phase DyCo2 on heating using a pressure differential scanning calorimeter (PDSC) in a hydrogen atmosphere between 0.1 and 5.0 MPa were investigated by a powder X-ray diffractometer (XRD), a differential scanning calorimeter under an argon flow atmosphere (Ar-DSC), a transmission electron microscope (TEM) and a hydrogen analyzer. As the temperature of DyCo2 increases, the reactions such as hydrogen absorption in a crystalline state, HIA (hydrogen-induced amorphization), precipitation of DyH3 and decomposition of the remaining amorphous phase into β-Co + DyH3 occurred exothermically for every hydrogen pressure. The mechanism of HIA in DyCo2 is discussed on the basis of the experimental results.
Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie
H.-W. Li et al., "Hydrogen-Induced Amorphization in C15 Laves Phase DyCo2 Studied by Pressure Calorimetry", Materials Science Forum, Vols. 475-479, pp. 2469-2472, 2005