Phase stability and elastic moduli of Cr2Nb by first-principles calculations

被引：108

作者：

Hong, S ^{[1
]}

Fu, CL ^{[1
]}

机构：

[1] Oak Ridge Natl Lab, Div Met & Ceram, Oak Ridge, TN 37831 USA

来源：

INTERMETALLICS | 1999年 / 7卷 / 01期

关键词：

Cr2Nb Laves phases; phase stability; first-principles calculations; FLAPW; elastic properties;

D O I：

10.1016/S0966-9795(98)00005-3

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The phase stability and elastic moduli of Cr2Nb are investigated by first-principles calculations. Heats of formation are calculated and compared for the three Laves phases (C15, C14, and C36). It is found that the C15 phase is the ground-state structure with the lowest energy and the C36 phase is an intermediate state between C15 and C14. These three phases, however, are very close in energy, indicating low stacking fault energies in this system. For the ground-state C15 phase, we calculate three elastic constants from which the shear and Young's moduli are obtained. It is found that these calculated moduli are smaller than the experimental values obtained from polycrystals. (C) 1998 Elsevier Science Ltd. All rights reserved.

引用

页码：5 / 9

页数：5

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