5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

Electromagnetic effect produced in alloy melt and dendrite growth under the action of a pulsed magnetic field are researched by experimental and simulation. Simulation results show that alternating gradient electromagnetic forces act on the melt in front of the interface of the growing dendrites and the maximum electromagnetic force appears near the front of the solid/liquid interface, which forms a local electromagnetic oscillation and a strong disturbing effect on dendrite growth. Experimental observation shows that the stable growth of dendrites was disturbed, which led to occurrence of columnar to equiaxed transition (CET) and refinement of solidified grains. In addition, the pulsed magnetic field also produces electromagnetic convection in the melt which promotes the CET. As the results, the dendrites are observably refined even to spheroidal grains with the pulsed magnetic field. The CA-FD calculation shows that the electromagnetic convection causes the primary dendrite to rotate in solidification process. Because of the interface front is subjected to the action of multi-directional melt flow, the optimal growth of crystal is inhibited, which leads to the formation of spheroidal grains solidification.