Thermo-mechanical FEM Analysis on Crack Prediction of Solidified Shell in Funnel-Shaped Mold

In this paper, a 3-dimensional mathematical model has been developed for the thermo-mechanical coupled analysis of the solidification process of carbon steel in funnelshaped mold using thermo-elastic-plastic finite element method (FEM). The major application of the model is to perform computations of temperature, stress and longitudinal cracking index (LCI) variations in shell. The effects of casting speed on stress and LCI are discussed. The results show that the temperature at the thin slab off-corner of wide face is higher than the temperature at the center of the wide face and narrow face, the temperature history at the thin slab off-corner appears two plateaus at 280 mm and 840 mm below meniscus, and the peak stress of solidification shell occurs at the region of funnel edge, where the shell has high cracking susceptibility. The LCI is high at the wideface center, funnel edge and off-corner of thin slab wide face. Increasing casting speed within certain range can decrease the LCI of original shell and reduce the possibility of longitudinal crack.