Modeling Solidification Microstructures of Steel Round Billets Obtained by Continuous Casting

Abstract

The knowledge of the position of the columnar to equaxial transition (CET) is of paramount importance to evaluate the internal quality of continuous casting (CC) products. One way to control the operational CC conditions with the objective of assuring a given quality level is to develop a numerical program able to calculate the local solidification rate (R), the local thermal gradient (G) and the local time of solidification (tf) and to relate these parameters to the CET by means of a predictive model. In the present investigation, the dendritic morphology and the CET transition of three round billets made of a low carbon steel (0.14%C) and produced by CC are characterized, and a computer model is developed to evaluate the R, G and tf-parameters. Referencing the well-known CET transition model developed by Hunt, a simple prediction equation is thus obtained for the steel under study and it is used to propose guidelines for the optimization of the CC operational parameters.

Compactness Degree of Longitudinal Section of Outer Columnar Grain Zone in Continuous Casting Billet Using Cellular Automaton-Finite Element Method

“…7,8) Recently, the CA (cellular automaton) model has considered the effects of fluid flow on the solidification process. 6) At present, there are a few models 3,5,7,8) using the CA method for simulating the solidification structure of continuous casting steel, but there are few examples 11) about investigating some special mechanisms of the solidification process of billet based on this method.…”

“…[1][2][3][4][5] Experiment method and simulation method are two very important ways to investigate the solidification structure. Although many experimental works have been carried out in order to obtain the optimum solidification process of continuous casting, it is also very desirable to establish mathematical models to simulate the evolution of the solidification structure.…”

Study of Solidification of Continuously Cast Steel Round Billets Using Numerical Modelling

“…On the other hand, CC of various steel grades requires individual processing parameters. Therefore, a fundamental task of the CC method is the optimization of the processing parameters in order to maximize the safety of the process, to improve the economy and ecology of the technology and mainly to increase the quality of the products [1][2][3][4][5].…”

Solidification Structure and Compactness Degree of Central Equiaxed Grain Zone in Continuous Casting Billet Using Cellular Automaton-Finite Element Method

“…1,4) The macrosegregation of the billet is closely related to the ratio of equiaxed grain zone in the billet, and the ways to increase the area ratio of the equiaxed grain zone has been proposed by many researchers. [1][2][3][4]10,11) However, the compactness degree of equiaxed grain zone has not yet been specially investigated. The compactness degree of equiaxed grain zone can be evaluated by the grain number or the grain size.…”

“…Therefore, both of them should be controlled properly during continuous casting process. [1][2][3][4] Although many experimental works have been carried out in order to obtain the optimum condition for solidification process of continuous casting, it is also very desirable to establish mathematical models to simulate the evolution of solidification structure. The simulation methods can be divided into deterministic models and stochastic models, which have been developed rapidly over the last couple of decades.…”