Effect of traveling magnetic field on freckle formation in directionally solidified CMSX-4 superalloy

Abstract In this study, the effects of magnetic field on freckle formation during directional solidification of CMSX-4 superalloy have been investigated for the first time. First of all, the direction and intensity of TMF were measured by experiments and simulations. Then, TMF was applied during the solidification. The results show that freckle defects were reduced under the TMF with a proper magnetic intensity. The effect of TMF on freckle formation can be attributed to the following aspects. The Lorentz force, on the one hand, acting on the liquid, changes the convection behavior, and then affects the shear force acting on dendrites and the remelting of dendrite arms by segregated liquid. On the other hand, the Lorentz force also acts on the dendrite arms directly, and thus affecting the fragment formation.