Deterministic shear-thickening polishing for surface morphology error correction

Abstract

Shear-thickening polishing is increasingly applied to the fine processing of precision component surfaces in CNC machining due to its efficient material removal rate, high-quality surface control, excellent adaptability to surface shapes, and flexible posture adjustment capability. With the precise control of the removal function and dwell time, the shear-thickening polishing method enables the simultaneous attainment of both extremely low surface roughness and ultra-high surface shape accuracy. A deterministic material removal and surface morphology error correction method in the shear-thickening polishing process was proposed. This method is mainly composed of a controllable effective combination calculation strategy for polishing points and an Iterative-NNLS (Non-Negative Least Squares) dwell time algorithm. By merging polishing points based on material removal amounts, the computational load of the algorithm was significantly reduced. Two polishing dwell time calculation algorithms were then sequentially employed to achieve smooth feed motion. Simulation results indicate that the new calculation strategy could reduce computation time by up to 86%, significantly enhancing the smoothness of dwell time. Experimental results demonstrate that the proposed deterministic shear thickening polishing surface morphology control method effectively reduced the surface PV value from 104 nm to 35 nm, achieving surfaces roughness close to Ra 1 nm and enabling high-precision control of the surface profile.