Anisotropy in interface stress at the BCC-iron solid-melt interface: molecular dynamics and phase field crystal modelling

Abstract

The interface stresses at of the solid-melt interface are, in general, anisotropic. The anisotropy in the interfacial stress can be evaluated using molecular dynamics (MD) and phase field crystal (PFC) models. In this paper, we report our results on the evaluation of the anisotropy in interface stress in a BCC solid with its melt. Specifically, we study Fe using both MD and PFC models. We show that while both MD and PFC can be used for the evaluation, and the PFC and the amplitude equations based on PFC give quantitatively consistent results, the MD and PFC results are qualitatively the same but do not match quantitatively. We also find that even though the interfacial free energy is only weakly anisotropic in BCC interfacial stress anisotropy is strong. This strong anisotropy has implications for the equilibrium shapes, growth morphologies and other properties at nano-scale in these materials.

arXiv comment32 pages, 10 figures and 52 references

References in corpus (9)

• Modeling Elasticity in Crystal Growth
• Modeling Elastic and Plastic Deformations in Non-Equilibrium Processing Using Phase Field Crystals
• Direct calculation of the hard-sphere crystal/melt interfacial free energy
• Free energy functionals for efficient phase field crystal modeling of structural phase transformations
• Phase-field crystal modeling of equilibrium bcc-liquid interfaces
• Phase-field-crystal model for fcc ordering
• Amplitude expansion of the binary phase field crystal model
• Ginzburg-Landau theory of crystalline anisotropy for bcc-liquid interfaces
• Phase-field-crystal models and mechanical equilibrium