Influence of Abrasive Hardness on Chemical Mechanical Polishing of 304 Stainless Steel

Abstract

In order to improve the quality in chemical mechanical polishing (CMP) of stainless steel and the material removal rate (MRR), 6 kinds of abrasives were used to do the CMP test of 304 stainless steel. In this paper, the 6 kinds of abrasives have different hardness. The experimental results show that, in the CMP process, the MRR increases with the increase of the abrasive hardness, the surface roughness decreases firstly and then raises with the increase of the abrasive hardness. This surface roughness reduces the lowest value when the chromium oxide (CrO) abrasive is used. With low-hardness copper oxide abrasives and magnesium oxide abrasives, it can only remove partial scratches on the surface during the polishing process and obtained low MRR and poor surface quality. Silica abrasives were easy to condense in the polishing slurry and the Gelation hindered the cutting action of abrasive, So resulting in low MRR and poor surface quality. The chromium oxide and white corundum, their hardness are close to the stainless steel, can remove the surface oxide layer of the sample while not produce the damage of the workpiece surface, so the surface quality was very well. Considering that chromium oxide contains Cr2+, it will pollute the environment. Therefore, in comprehensive consideration of the surface quality and MRR, take the white corundum as an abrasive in the CMP of 304 stainless steel.