Effect of external magnetic field on morphology and microstructure of wire arc additive manufacture

The longitudinal magnetic field assisted CMT+P process is used for arc fuse additive manufacturing of aluminum alloy. Analyze the forming and organization properties of additive components. The excitation frequency is 40Hz ~ 70Hz, and the excitation current is 4A ~ 8A, during the additive manufacturing process. The results show that the external magnetic field can improve the forming and organization properties of the material, but the size of the magnetic field has a reasonable matching interval. The optimal parameter is when the excitation frequency is 50Hz and the excitation current is 5A. The influence of the magnetic field promotes the flow process in the molten pool, increases the homogenization of alloying elements, reduces the temperature gradient and promotes the equiaxed crystallization and refinement of crystal grains. The surface tension of the molten pool is weakened under the action of an external magnetic field. The size and frequency of the magnetic field affect the stability of the molten pool flow and the crystallization of the molten pool.