Deformation of the strand shell during peritectic transfomation
As The high susceptibility of peritectic steel grades to hot tearing is a well known problem in metallurgy. It easily happens along the dendrites and grain boundaries on mush zone. If hot tears form between zero ductility temperature and liquid impenetrable temperature, they cannot be refilled with the surrounding liquid and cracks will be formed. Also as is well known that, during continuous slab steel casting, the mold wall is made tapered to remain in contact with the shell of steel due to the thermal mechanical behavior of the solidifying shell. Due to the complexity of those problems, the resulting deformation of the strand shell is not well understood till today.
We successfully simulate the peritectic transformation by MICRESS software using multi-phase field methods. Due to the memory restriction in Abaqus, mesh rediscretization subroutines which are needed to increase the mesh size and reduce the number of elements are developed to couple the MICRESS and Abaqus software. Using the advantage of phase-field method, we can simulate the micro evolution of slab casting to get the structure for finite element method analysis. Stress and strain distributions are calculated by Abaqus with the processing conditions from industry. To calculate the shrinkage, thermal shrinkage, solutal shrinkage and lattice contraction during phase transformation are taking into account. The results show the regions which have high possibility to form cracks and also the total shrinkage during the solidification which is comparable with the experiments. Those simulations demonstrate a new way to simulate and understand the slab casting processing. Due to the limitations, we will continue with OpenPhase for further use.