Numerical simulation of non-dendritic structure formation in Mg-Al alloy solidified with ultrasonic field.

The formation of non-dendritic structure of Mg alloy solidified with ultrasonic treatment was investigated by numerical simulation and experiment. The models of nucleation and crystal growth involved the effects of ultrasonic cavitation and acoustic streaming were built. Based on the models, the grain refinement and the microstructure change from dendrite to non-dendritic structure of a Mg-Al alloy were numerically simulated by cellular automata method.