International Journal of Iron & Steel Society of Iran

International Journal of Iron & Steel Society of Iran

The Effect of Carbon Content on the Solidification of Steel Slab in the Continuous Casting Process: A Numerical Simulation Case Study

Document Type : Research Paper

Author
Department of Materials Science and Engineering, Sharif University of Technology, Tehran, Iran
Abstract
 In this study, the effect of carbon content, the primary element in the chemical composition of carbon steel grades, on the solidification of steel slabs is investigated using a numerical simulation approach. Three commercial carbon steel grades with varying carbon contents are selected. Technological and operational conditions, such as slab geometry, water flow rates of spray nozzles in the secondary cooling zone, mold features, casting speed, and the temperature of spray cooling water in the secondary cooling zone, are held constant and based on a real industrial continuous slab casting machine. The thermophysical properties of each steel grade are computed based on the calculation of phase diagrams (CALPHAD). The numerical simulation of the process is then conducted by solving the heat transfer equation (coupled with the CALPHAD-based thermophysical properties) based on computational fluid dynamics (CFD) simulated in the MATLAB environment. Parameters such as metallurgical length and solid shell thickness profiles are calculated and compared over time for various steel grades. In addition, the factor K in the famous square root function for solid shell thickness (as a function of time) is determined and analyzed for each grade. This study demonstrates that increasing the carbon content decreases the metallurgical length. As carbon content decreases, the thickness factor K increases in carbon steel grades. 
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