Thermosolid Coupling Analysis And Microtissue Simulation Of Continuous Casting Solidification Process

The introduction of continuous casting technology has significantly increased the efficiency of steel production.In this context,the question of how to improve the quality of continuous cast billets has become a widespread scientific concern and an urgent problem to be solved.The quality of the profile is influenced to some extent by the quality of the billet,which also depends on the solidification behavior of the steel in the various cooling phases and on the microstructure of the solidification.In order to provide a theoretical basis for production in this area,this paper examines two aspects: optimization of the process in the solidification phase and improvement of the microstructure during solidification of the billet.In this paper,a rectangular continuous casting ingot No.50 from Tangshan steelworks is used as the object of study.Through numerical simulation,the parameters of the continuous casting process are optimised in three aspects: thermal coupling in the mould,simulation of the whole steady-state solidification process and solidification organisation of the ingot using Pro CAST large-scale casting process simulation software.Mile’s algorithm was used to simulate the coupled temperature and stress fields in the mould and observe the effect of changes in process parameters on the stress pattern during continuous casting.The study shows that the corners cool the fastest,solidify first and are subjected to the highest stresses due to simultaneous cooling in both directions.Increasing the casting temperature can reduce the stresses at several points on the billet surface,but the overall effect is negligible;increasing the drawing speed can also reduce the surface stresses,and the effect is relatively large.During the steady-state simulation,the solidification process of the continuous casting billet was analysed in conjunction with the secondary development software,and the effect of various process parameters on the length of the liquid phase cavities and the location and size of the paste zone in the billet was investigated.The mechanism of crack formation was analysed and the ratio of water to cooling water in the secondary cooling zone was adjusted to eliminate the serious phenomenon of surface heating in the secondary cooling zone.The results show that lower casting temperature,higher drawing speed and lower cooling intensity in the secondary cooling zone can increase the proportion of equiaxed crystals and reduce the average grain size,affecting the temperature distribution at the solidification front of the cast billet.Electromagnetic stirring can increase the proportion of equiaxed crystals,which can contribute to improved grain size.