Numerical simulations and experiment on melt flow and solidification in ingot casting process with bilateral double vertical linear electromagnetic stirring in riser

A bilateral Double Vertical Linear Electromagnetic Stirring in the ingot riser (Riser-DV-LEMS) method was proposed to avoid magnetic shielding of thick-walled iron mold. As a physical simulation experiment of applying Vertical Linear Electromagnetic Stirring (V-LEMS) at the Incoloy 800H ingot top show that V-LEMS can effectively enhance melt flow and mixing of molten steel in ingot, changes the morphology of liquid core, and significantly improves the ingot center quality, thereby verifying the effectiveness of the Riser-V-LEMS method. A three-dimensional numerical simulation model coupled with electromagnetic field, melt flow and solidification was established to study the molten steel flow and solidification behavior of 420 mm × 420 mm × 0.78 m ingot under Riser-DV-LEMS. Numerical simulations results show that the electromagnetic force in the ingot riser can effectively drive the molten steel to flow along bilateral sides of the ingot riser wall and act on the central zone, thereby promoting the flow throughout the entire cross section, so that it avoids the drawback of the unilateral V-LEMS that fails to drive the melt flow on the opposite side of large-diameter ingots. The temperature distribution along the entire solidification front of ingot becomes more uniform, which increases the width and intersection angle of liquid core front, and decreases its depth, thereby making the morphology of the liquid-solid interface become flat and enhancing the feeding ability of molten steel from the riser to the central region, which is beneficial to reduce shrinkage cavities, porosity and macrosegregation and improve the quality of ingot.