关键词: 半固态金属, 微观组织, 相场法, 模拟, 电磁搅拌法

Abstract: In the process of preparation of semi-solid metal materials, a variety of factors would influence the prepared time, the morphology of non-dendritic microstructure. The aim of this work is using phase-field method to simulate non-dendritic growth during preparation of Al-4Cu-Mg semi-solid alloy adopting electromagnetic stirring method (EMS method). Several affecting factors such as the disturbance intensity, the anisotropy, the thickness of the interface and the ratio of diffusivity in solid and liquid, etc are considered. It is shown that decreasing the thickness of the interface results in more circular outline perimeter of particles, and increasing the diffusivity in solid can reduce degree of microsegregation. The disturbance intensity in the model can be connected with current intensity of stator or magnetic induction density impressed. Simulation results show that the larger the disturbance intensity or magnetic induction density, the smaller the size and the more globular morphology of original phase in the matrix.

Key words: semi-solid metal, microstructure, phase-field method, simulation, electromagnetic stirring method