Scaling of alloy interfacial properties under compositional strain

Abstract

Complex morphologies and microstructures that emerge during materials growth and solidification are often determined by both equilibrium and kinetic properties of the interface and their crystalline anisotropies. However limited knowledge is available for the alloying and particularly the compositionally generated elastic effects on these interface characteristics. Here we systematically investigate such compositional effects on the interfacial properties of an alloy model system based on the phase-field-crystal analysis, including the solid-liquid interfacial free energy, kinetic coefficient, and lattice pinning strength. Scaling relations for these interfacial quantities over various ranges of material parameters are identified and predicted. Our results indicate the important effects of couplings among mesoscopic and microscopic length scales of alloy structure and concentration, and also the influence of compressive and tensile interface stresses induced by composition variations. The approach developed here provides an efficient way to systematically identify these key material properties beyond the traditional atomistic and continuum methods.