Mathematical modelling of the continuous casting of blooms and beam blanks
Metallurgical and Materials Engineering Department, School of Engineering, Federal University of Minas Gerais, Av. Presidente Antônio Carlos 6627, 31270-901 Belo Horizonte, Brazil.
Defects and discontinuities generated in continuous casting are directly related to heat transfer during the process and the stresses to which the material is subjected. Knowledge of these phenomena is essential for both process safety and the quality of the final product. The aim of this work is to analyze the thermo-mechanical behavior of blooms and beam blanks during continuous casting. The continuous casting machine considered in this study is used to cast both blooms and beam blanks. The secondary cooling can be divided into cooling zone z0, cooling zone z1, cooling zone z2, and cooling zone z3. For each geometry, there are specific molds, z0, z1, z2 (sprays and support rollers), which need to be replaced when there is a geometry shift. The changing of the cooling segments brings security risks for the operators and reduces the continuous casting availability. Therefore, it is desired to have a common z2 for both blooms and beam blanks to reduce operational risk exposure and increase the machine production rate. For this to be possible, it is necessary to assess the temperature and resistance of the solidified skin, the effects of thermal stresses, ferrostatic pressure, and contact stresses. This work is the first step in this study. A thermo-mechanical model was developed for both geometries. The thermal model was verified by temperature measurement and shell measurements of blackouts. Finally, the results were analyzed and compared.
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