Stacking fault energy of the NbCr2 Laves phase

摘要

A total energy study has been performed on the NbCr2 Laves phase using first-principles electronic structure calculations based on the full-potential linear muffin-tin orbital method. For the two Laves phase structures, C15 and C14, cohesive energies and heats of formation were obtained. A method was developed to calculate the stacking fault energy, y, in C15 Laves phases, using only two quantities: the cohesive energy difference between C15 and C14 Laves phases, and the C15 lattice constant. For C15 NbCr2, the calculated stacking fault energy is 90mJm~2. The calculated result is in good agreement with an experimental result deduced from an extended dislocation node.