Relationship between grain boundary segregation and grain boundary diffusion in Cu-Ag alloys
R.K. Koju, Y. Mishin
Abstract
Segregation of alloy components to grain boundaries (GBs) and the drastically accelerated atomic mobility in GB regions are two phenomena of significant fundamental interest and technological importance. Surprisingly, the relationships between them remain virtually unexplored. In this paper, atomistic simulations are applied to understand the effect of GB segregation on GB diffusion using a Cu-Ag alloy as a model. It is shown that GB segregation can cause acceleration or reduction in GB diffusivity of the alloy components, depending on the amount of segregation, temperature, and alloy composition. The diffusion-segregation interplay can be explained by the site-blocking effect and the GB premelting at high temperatures.
Topics & Concepts
Grain boundaryMaterials scienceGrain boundary diffusion coefficientAlloyDiffusionPremeltingLattice diffusion coefficientMolecular dynamicsLattice (music)Condensed matter physicsThermodynamicsMonte Carlo methodChemical physicsCrystallographyEffective diffusion coefficientMetallurgyMicrostructureComputational chemistryPhysicsChemistryMedicineRadiologyAcousticsMagnetic resonance imagingStatisticsComposite materialMathematicsMelting pointMicrostructure and mechanical propertiesAluminum Alloy Microstructure PropertiesHigh Temperature Alloys and Creep