Speaker
Description
A dynamic permeability model based on real-time local solidification time (LST) is proposed to improve macrosegregation prediction in alloy directional solidification. By tracking the solidification history of each computational cell with a state-machine algorithm, the model dynamically updates the secondary dendrite arm spacing (SDAS) using an experimental LST–SDAS relationship and evaluates permeability via the generalized West model. The mushy zone parameter and back-diffusion parameter are then derived from the permeability and the Clyne–Kurz model, respectively, thereby establishing a direct bidirectional coupling relationship between micro-component transport and macro-flow and heat transfer. The model is validated against electroslag remelting experiments of 40CrNi2Mo steel. Compared with a constant permeability model, the proposed model reduces the root‑mean‑square error of carbon macrosegregation predictions by over 70% and increases the coefficient of determination from 0.498 to 0.865, demonstrating significantly improved accuracy.
| Speaker Company/University | Institute of Metal Research, Chinese Academy of Sciences |
|---|