Revisiting dynamics and models of microsegregation during polycrystalline solidification of binary alloy

Microsegregation formed during solidification is of great importance to material properties. The conventional Lever rule and Scheil equation are widely used predict solute segregation. However, these models always fail the exact concentration at a high solid fraction because theoretical assumptions. Here, dynamics microsegregation polycrystalline refined Al-Cu alloy studied via two- three-dimensional quantitative phase-field simulations. Simulations with different grain refinement level, cooling rate, diffusion coefficient demonstrate that segregation end (i.e. when close unit) not strongly correlated morphology back diffusion. These independences in accordance which only relates fraction, but model predicts much higher liquid than Accordingly, based on simulations, new analytical derived. Unlike or respectively overestimates underestimates concentration, present pretty good agreement particularly late stage.