Simulation of surface deformation control during selective laser melting of AlSi10Mg powder using an external magnetic field

Abstract

Selective laser melting (SLM) produces complex physical behaviors. After laser melting, the molten pool condenses with an uneven surface, which influences the next powder spreading process and affects the quality of the final product. This phenomenon is mainly caused by the Marangoni effect, which is generated by the surface tension of the liquid. This paper describes a method to control the surface deformation during the SLM of AlSi10Mg powder. It is assumed that there is a magnetic field (MF) added to the alloy powder generating a Lorentz force in the molten pool (MP). The Lorentz force can decrease the impact of the Marangoni effect and change the velocity field. Our work simulates the AlSi10Mg alloy melting process, and analyzes the physical parameters of the MP with or without an MF. It is found that increasing the MF within a certain range decreases the impact of the Marangoni effect, resulting in a smoother surface.