Chemical Mechanical Lapping of 316 Based on Solid-Phase Fenton Reaction

To achieve both a high material removal rate and excellent surface quality, this paper proposes a solid-phase Fenton chemo-mechanical lapping (SF-CML) method. Using high-purity type 316 stainless-steel as the research object, a solid lapping tool containing Fe₃O₄ microparticles was employed in synergy with an H₂O₂-based slurry. Under locally high-pressure and high-temperature conditions, Fe²⁺ ions are released, which in turn catalyze the generation of highly reactive hydroxyl radicals (·OH). These radicals promote the formation of an oxide layer on the workpiece surface, which is continuously removed through mechanical action. The results show that at pH 2.5 and an H₂O₂ concentration of 0.05 wt%, SF-CML achieves the best processing performance, with an MRR of 16.64 μm/min and a Sa as low as 20.95 nm. XPS, EPR, and other characterization methods collectively provided evidence for the oxidation of the sample surface and the existence of ferrous ions and hydroxyl radicals in the slurry, thereby confirming the effectiveness of the solid-phase Fenton reaction. Compared with conventional homogeneous Fenton CMP and pure mechanical lapping, SF-CML not only significantly improves removal efficiency but also effectively enhances surface quality. This method avoids the problems of easy precipitation and low removal efficiency commonly encountered in traditional homogeneous Fenton systems, providing a new technical pathway for high-efficiency precision processing of metallic materials.