Atomistic modeling of metal-nonmetal interphase boundary diffusion

Abstract

Atomistic computer simulations are applied to investigate the atomic structure, thermal stability, and diffusion processes in Al-Si interphase boundaries as a prototype of metal-ceramic interfaces in composite materials. Some of the most stable orientation relationships between the phases found in this work were previously observed in epitaxy experiments. A non-equilibrium interface can transform to a more stable state by a mechanism that we call interface-induced recrystallization. Diffusion of both Al and Si atoms in stable Al-Si interfaces is surprisingly slow compared with diffusion of both elements in Al grain boundaries but can be accelerated in the presence of interface disconnections. A qualitative explanation of the sluggish interphase boundary diffusion is proposed. Atomic mechanisms of interphase boundary diffusion are similar to those in metallic grain boundaries and are dominated by correlated atomic rearrangements in the form of strings and rings of collectively moving atoms.

References in corpus (1)

• Relationship between grain boundary segregation and grain boundary diffusion in Cu-Ag alloys

Cited by in corpus (3)

• Atomistic modeling of diffusion processes at Al(Si)/Si(111) interphase boundaries obtained by vapor deposition
• Magnesium-graphene interphase boundaries created by high-pressure torsion enhance hydrogen storage kinetics:Mechanisms and significance of activation energy and frequency factor
• The origin of strings and rings in the atomic dynamics of disordered systems