Exploring the nano-polishing mechanisms of Invar

Abstract With the rapid development of nano-polishing technology, ultra-precise micro-nano components require tighter tolerances for the surface engineering of the Invar alloy. Due to its low hardness and high chemical activity, it is a challenge to reveal the nano-polishing mechanism experimentally. In this work, we studied the effect of polishing parameters on the nano-polishing properties of Invar by molecular dynamics simulation, and experiments were conducted to verify the simulation results. Our findings indicate that higher polishing speed and shallower polishing depth with optimized rolling torque can lead to a reduction of the subsurface damage layer thickness as well as an improvement in polishing efficiency and surface quality. The nano-polishing mechanism is revealed, showing that effective removal occurs only in the plowing regime and the cutting regime, which require sufficient rolling and sliding depths, respectively. Furthermore, an analytic removal theory was developed that excellently describes and predicts the polishing behavior of Invar. This work provides a guideline for improving the polishing precision, surface quality, and material removal efficiency for Invar work pieces.