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arXiv · 1104.5143

First-principles calculations on temperature- dependent elastic constants of rare-earth intermetallic compounds:YAg and YCu

Wang Rui·Wang Shaofeng·Wu Xiaozhi·Yao Yin
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Abstract

we present the temperature-dependent elastic constants of two ductile rare-earth intermetallic compounds YAg and YCu with CsCl-type B2 structure by using a first-principles approach. The elastic moduli as a function of temperature are predicted from the combination of static volumedependent elastic constants obtained by the first-principles total-energy method with density functional theory and the thermal expansion obtained by the first-principles phonon calculations with density-functional perturbation theory. The comparison between our calculated results and the available experimental data for Ag and Cu provides good agreements. In the calculated temperature $0-1000K$, the elastic constants of YAg and YCu follow a normal behavior with temperature that those decrease with increasing temperature, and satisfy the stability conditions for B2 structures. The Cauchy pressure for YAg and YCu as a function of temperature is also discussed, and our results mean that YAg and YCu become more ductile while increasing temperature.

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Wang Rui, Wang Shaofeng, Wu Xiaozhi, Yao Yin. 2011-04-27. First-principles calculations on temperature- dependent elastic constants of rare-earth intermetallic compounds:YAg and YCu. https://arxiv.org/abs/1104.5143

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