论文信息 - The lattice stability and structure of delta -UZr2 at elevated temperatures

The lattice stability and structure of delta -UZr2 at elevated temperatures

The lattice stability and structure of delta -UZr2 were studied by thermal analysis and high-resolution neutron diffraction techniques. The delta structure was confirmed to be the modified C32 (AlB2-type) structure as in the omega phase of Zr. The temperature dependence of the lattice parameters in the delta phase was determined between room temperature and 880 K. The heat effects at the phase transition from delta to BCC solid solutions were determined to be 5.6-4.4 kJ g-atom-1 for XZr=0.67-0.81. From the composition dependence, the transition enthalpy from omega to beta (BCC) phase in pure Zr was estimated to be 2.8 kJ g-atom-1.

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