Growth and mechanical properties of a MoC precipitate at a Mo grain boundary: An \textit{ab initio} density functional theory study
Rebecca Janisch and Christian Els\"{a}sser

Atomic-scale stages of the growth of an interfacial precipitate film of tetragonal molybdenum carbide at a $\Sigma$5 (310) [001] symmetrical tilt grain boundary in body-centered cubic molybdenum were investigated by means of atomistic supercell calculations on the basis of ab-initio density functional theory (DFT). The structural development of the precipitate with increasing carbon concentration is analysed qualitatively and quantitatively. The structurally optimized atomistic model for the fully developed precipitate is compared to experimental high-resolution images from transmission electron microscopy. Characteristic interface energies are calculated to evaluate the influence of the precipitate on the mechanical stability of the material. Finally, an atomic-scale twinning mechanism in the MoC precipitate is proposed.

© 2008 The American Physical Society.