Fluid-structure interaction simulation based physicochemical synergistic removal modeling and process optimization for wheel-type elastic emission machining.

Wheel-type elastic emission machining (EEM) holds great promise for achieving atomic-level, low-damage optical fabrication. However, existing material removal models fail to account for the inherently coupled physicochemical removal mechanism of EEM, leaving deterministic process control a challenge. In this study, a physicochemical synergistic material removal model was developed for wheel-type elastic emission machining, and an optimal process window was established. A three-dimensional fluid-structure interaction (FSI) simulation model was constructed to resolve the fluid pressure, wall shear stress, and velocity distributions at the polishing interface, while simultaneously capturing the elastic deformation of the polyurethane polishing wheel. The results confirm that the predicted removal profiles are in excellent agreement with the experimental measurements, with coefficients of determination exceeding 0.99 in both the XZ- and YZ-planes. Experimental investigations revealed a three-stage nonlinear response of removal depth to polishing speed, polishing time, and polishing gap. Normalized sensitivity analysis indicated that polishing time is the dominant factor, followed by the polishing gap and polishing speed. A hierarchical optimization framework was adopted, in which efficiency served as a hard constraint and stability was maximized among all qualified candidates. The resulting optimal process window achieves a synergistic balance between high removal efficiency and disturbance rejection. This work provides reliable process guidance for the application of wheel-type EEM to atomic-level fabrication of ultra-precision optical surfaces.