Chemical magnetic field-assisted batch polishing method of 316L stainless steel

316L stainless steel has been extensively employed in the manufacturing of medical equipment and biomedical implants because of its good ductility, corrosion resistance and biocompatibility, etc. However, there has always been a non-neglected problem of low polishing precision and efficiency in the whole machining chain for such parts, hence, it is difficult to meet the batch demand of the market for 316L stainless steel with high-precision surface. Based on the principle of magnetic field-assisted batch polishing (MABP) proposed by our research team previously, a novel chemical magnetic field-assisted batch polishing (CMABP) method here is developed by adding chemical reagents (i.e., the mixture of oxalic acid and hydrogen peroxide) in the preparation process of regular magnetic brush, desiring and expecting to further realize the polishing of 316L stainless steel with higher precision and efficiency simultaneously. The preliminary experimental results demonstrated that the value of surface roughness Sa after CMABP became smaller and the material removal rate increased comparing to that after MABP, which did verify the potential advantage of the established CMABP approach. In detail, CMABP experiments with pH value and H 2 O 2 concentration as variables were carried out quantitatively. The results suggested that, within the set range of pH value (from 2 to 7) and H 2 O 2 concentration (from 0.3 wt.% to 2.0 wt.%), when pH was chosen as 4 and H 2 O 2 concentration was adjusted as 2.0 wt.%, the value of Sa after CMABP was the minimum, which could be 38% lower than that of MABP approximately. Nonetheless, material removal rate reached to the maximum, which could be around 168% more than that after MABP, when pH and H 2 O 2 concentration were determined as 3.0 and 2.0 wt.%, respectively. Additionally, the discrepancy between the chemical and the regular magnetic brushes were detected and analyzed comparatively both at macro and micro scales. Also, the products on the surface of 316L stainless steel, such as the weak-binding layer and the passive layer, were discovered and taken to interpret the experimental phenomena of the surface roughness and material removal rate varying with the content of chemical reagents in CMABP, thereby revealing the material removal mechanisms correspondingly and interestingly. This work is capable of providing valuable reference undoubtedly for batch precision polishing of 316L stainless steel and other significant functional materials.