SIMULATION OF SOLIDIFICATION STRUCTURE AND CET PROCESS IN HIGH SILICON STEEL BASE ON A CAFE METHOD

摘要

The solidification microstructure in high silicon steel was simulated based on the CAFE method. The simulation results are consistent with the experimental findings. The evolution of temperature and solid fraction during the solidification were compared and discussed. The casting of high silicon steel is a stepwise solidification mode under air cooling condition. The columnar-to-equiaxed transition (CET) was researched in the CAFE model. The CET in the solidification process is not abrupt but occurs gradually. In addition, the influence of superheat on the microstructure and CET of the casting were also studied in detail. The results show that for the decreased in superheat, the ratio of columnar dendrite zone decreased, the mean surface area of gain decreased, and the CET occurs ahead of schedule. The thermal gradient plays a decisive role in the CET process.