Effect of Temperature Variations, Thermal Stresses and Region of ‎Meniscus of Copper Mold on Quality of Billet Produced by Continuous Casting Process of Steel

The optimal quality of continuous casting is always one of the main concerns in the steel industry. ‎Copper mold is one of the main components of the continuous casting of steel. The physical, chemical and ‎mechanical phenomena that occur in the near-meniscus region play an important role in the surface ‎quality of the ingot. In this paper, several effective parameters including the effect of lubrication on the ‎mold surface, the formation of the meniscus and the formation of a specific type of galvanic cell on the ‎quality of the ingot have been investigated. According to the theory of molten ionic structure and ‎analysis of metallurgical slag, it can be said that the molten slag phase of the mold powder is an ionic ‎liquid (copper/iron), so that in the powder produced by stollberg, the force is driven to 1.9 volt. Based ‎on the cooling parameters of the copper mold, a three dimensional calculation model was created and a ‎three dimensional temperature, stress and thermal strain distribution was simulated numerically using ‎the finite element method (FEM) and the maximum deformation of the copper mold was about -0.04 ‎mm, The highest internal temperature of the copper tube is 2200°C and the maximum thermal stress of ‎‎390MPa. Based on the results, the largest difference in temperature from top to bottom of the mold is ‎not more than 10 degrees, and the maximum thermal deformation of the copper mold appears at a ‎position 30 mm below the meniscus, but not strong enough to cause cracking. In addition, the effect of ‎powder with different alkalinity on the characteristics of the oscillating marks on the surface of the ‎ingot was considered. Based on microscopic images of oscillation symptoms, it can be said that the use ‎of Scorialit powder makes the swinging signs shorter and with a lower depth than using the Accutherm ‎powder.‎