| Abstract Scope |
Characterizing mass transport under severe thermal and concentration gradients is critical to predicting phase stability in tungsten-chromium (W–Cr) alloys. Advancing our previous parallelized, fluctuation-governed Cahn–Hilliard phase-field framework [Geng et al., MSMSE 34, 015012 (2025)], we introduce a 3D, divergence-based Kinetic Monte Carlo (KMC) reformulation of the model. By transforming the continuous, deterministic Cahn–Hilliard equation into a discrete, stochastic, flux-based KMC solver, this framework uniquely decouples and quantifies time-dependent driving forces. Specifically, it explicitly tracks whether microstructural evolution at any given period is driven by concentration, temperature, or interfacial energy fluxes. Incorporating a Redlich–Kister free energy function for the experimental W–Cr miscibility gap and a coupled thermomigration function for the Soret effect, this hybrid approach provides an unprecedented mechanistic look into 3D spinodal decomposition, nucleation, and morphological stability under extreme conditions. |