ANALYSIS OF ELECTROMAGNETIC FIELD AND JOULE HEATING OF ELECTROSLAG REMELTING PROCESSES

A 3D finite element model was developed to simulate the magnetic field, electromag- netic force, current density and Joule heating of electroslag remelting processes (electrode, slag and ingot) by using of Maxwell equation, Lorentz law and Joule law. Especially, the skin effect is shown and discussed based on numerical results. The results show that the current distribute on the external surfaces of slag and ingot. In slag, due to the low electrical conductivity of slag, the current distribution changes, gathering on the end of electrode. The maximum electromagnetic force is at the upper surface nearby the electrode and the maximum joule heating is at the interface of electrode and slag. When current frequency is greater than 35 Hz, the vortex flow will occur in interior of electrode and ingot. When electrode immersion depth increase and slag cap thickness decrease, the maximum of the joule heat in slag will increase.