Continuous casting is widely used for production of steel slab. The main problem is that if the stress and strain exceed a threshold value, steel slab will be cracked as the layer of steel slab depends on variable thermodynamic load in the solidification process.
The main cause of steel slab crack is the thermal stress that is generated by uneven temperature distribution during the solidification of molten steel.
Ri Yong Hwa, a researcher at the Faculty of Aerospace Engineering, proposed a method of determining the optimum heat transfer coefficient to prevent thermal crack of slab, on the basis of the identification of the cause of crack by analysis of unsteady thermal stress in the continuous casting of the slab whose width is relatively long for its height.
He analyzed unsteady temperature field and thermal stress of 800×150mm2 steel slab in the continuous casting process by using ANSYS to find out the reasons why steel slab is cracked. The analysis revealed that the reason is that the layer is not thick enough to withstand the thermal stress and the static pressure of the molten steel in the height direction of this band, and that all the thermal stresses on the surface exceed the yield limit of 1.9Mpa.
Then, based on the band analysis data and the optimization algorithm in the continuous casting process, he determined the reasonable coefficient of band heat transfer to prevent the crack of the steel slab by using ANSYS-workbench.
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