Initial Solidification Control of Continuous Casting Using Electromagnetic Oscillation Method

Abstract

An initial solidification control technology, called the Electromagnetic Oscillation Method, intermittently applying high frequency magnetic field was developed aiming to reduce the friction between mold and initial solidified shell and to perform high speed casting for producing cast having excellent surface properties. According to the method, a high frequency magnetic field is applied synchronizing with the mold oscillation, applying a horizontal and inward electromagnetic force from outside the mold during the positive strip period, while applying a downward electromagnetic force from above the mold during the negative strip period. The method was investigated in terms of influence on the surface properties of cast and other variables by applying the method to laboratory scale continuous steel casting. The experiment was given by casting round billets having 100 mm in diameter at casting speeds of 0.5 to 1.6mm/min, applying high frequency magnetic fields of 1 to 9.8 kHz. The flux film thickness in the mold increased by applying horizontal electromagnetic force during the positive strip period, and the surface properties of the cast improved. By applying downward electromagnetic force during the negative strip period, the strength of initial solidified shell increased to prevent the occurrence of breakout.