| Abstract Scope |
Based on the established dendritic-equiaxed & columnar macrosegregation model, a four-phase solidification model that further consider the gas phase, which supplements the volume reduction of solidification shrinkage, has been established to realize the prediction of shrinkage. For the prediction of inclusion, in order to distinguish the difference between exogenous and endogenous inclusions, two models had been established respectively: 1) for exogenous inclusions, the coupling of Discrete Phase Model (DPM) and four-phase solidification has been considered, which has the possibility to track the moving of inclusion particle; 2) for endogenous inclusions, inclusion-combined macrosegregation model, which coupling the inclusion growth theory with the multicomponent four-phase solidification model, has been established. This multi-defects model has been implemented on the solidification process of steel ingot to investigate the formation process of macrosegregation, shrinkage cavity, porosity, and inclusion defects. The strong interaction behaviors between the shrinkage cavity, inclusion and macrosegregation had been observed. |