Modeling of adhered powder particles and waviness on additive manufacturing part surface in electrochemical polishing

Abstract

An innovative approach in electrochemical polishing (ECP) has been developed to enhance surface quality and precision in post-processing additive manufacturing surfaces, with a particular focus on leveling adhered powders and mitigating surface waviness. This study introduces a novel 2D model for quantitatively simulating the material removal process of spherical powder residues and waviness on sintered surfaces, utilizing adaptive triangular meshing technology. The initial geometric profiles of surface defects were modeled using the ellipse equation for spherical powder particles and the sine function for surface waviness. Key profile control nodes were tracked to observe changes over time, with detailed analyses of electric field strength, current density, material removal thickness, and removal rate. Predictive modeling results indicate that the electric field direction remains parallel to the surface, and the current density is approximately 0.23A cm⁻² after ECP, achieving a consistent material removal rate of 0.28 μm min⁻¹ during polishing. Surface roughness measurements, taken over a sampling length of 500 µm, showed a reduction from Ra 3.74 μm to Ra 0.21 μm, and the comparison of simulated and experimental surface profiles was presented with an error of only 0.04 μm, demonstrating the method’s efficacy in finishing both adhered powders and waviness. This study provides a new perspective to investigate the mechanism of ECP additive manufacturing parts.