International Journal of Iron & Steel Society of Iran

International Journal of Iron & Steel Society of Iran

Investigation of Mushy Zone Formation and Its Characteristics During Continuous Casting of Steel Billets with A Simple Modeling and Simulation Process

Document Type : Research Paper

Author
M. Alizadeh
Department of Materials Science and Engineering, School of Engineering, Meybod University, Meybod, Yazd, Iran
10.22034/ijissi.2025.2048426.1313
Abstract
In this research, simple modeling and simulation were used, and the dimensions and characteristics of the mushy zone in medium carbon steel during continuous casting were investigated. For this purpose, a numerical solution of the heat transfer equation as well as analytical microsegregation equations were used, and the following items were determined as mushy zone characteristics: mushy zone width, mushy core, mushy zone area, overall and local solidification time, local cooling rate, and brittle region characteristics. The width of the mushy zone increases up to a certain point along the length of the billet and then decreases to zero. The length of the billet over which the width of the mushy zone decreases from a maximum value to zero is called the mushy core in which the temperature gradient increases at an increasing rate. As the distance from the meniscus rises, the local solidification time in the mushy zone increases linearly, and the cooling rate of this zone decreases rapidly. Overall and local solidification rate decreases throughout the billet length, but the local solidification rate experiences a sudden increase at the beginning of the mushy core. The behavior of brittle zone width is similar to that of the mushy zone, but the slope of its decrease is much greater. 
Keywords
Continuous casting
Billet
Mushy zone
Medium carbon steel
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