One-step hybrid adaptive polishing using shear-thickening fluid for nanometric surface finish on additively manufactured metallic surfaces

Achieving nanometric surface finish on additively manufactured parts with high roughness and complex geometries typically requires multiple polishing steps with low efficiency. This paper presents a one-step hybrid adaptive polishing method that integrates a flexible polishing tool with a bonded diamond abrasive cloth and a shear-thickening Al₂O₃ slurry fluid, enabling both shape adaptive and a seamless transition from two-body to three-body material removal. Experiments on stainless steel and titanium alloy demonstrate one-step polishing with arithmetical mean height below 50 nm. Mechanism analysis reveals that the dynamic balance between contact and fluid pressures drives wear- state evolution, achieving nanometric surface finish.