Hydrogen-Induced Amorphization in C15 Laves Phase DyCo2 Studied by Pressure Calorimetry


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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.



Materials Science Forum (Volumes 475-479)

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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

Online since:

January 2005




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