Surface integrity of bearing steel element with a new high-efficiency shear thickening polishing technique

Abstract

The bearing steel elements with high quality surface are required to improve the performance of bearings. A new high-efficiency shear-thickening polishing (STP) technology was used on bearing steel element ultraprecision machining. A kind of high efficiency shear thickening polishing slurry (HE-STPS) was prepared by mechanical mixing and ultrasonic dispersion method. The polishing experiments were carried out on a new intelligent polishing machine (HE-STP-II). The surface integrity of bearing steel element was studied by scanning electron microscopy (SEM), laser profilometer and some micro-scale test devices, then surface roughness and profile accuracy from sample surface were measured. Surface roughness decreases slightly as SiO2 size reaches nanoscale, which is related to the cutting depth of individual abrasive. The HE-STP would be a continuous process of wear, whose complex machining mechanism including micro-cutting, adhesive wear and other machining mechanism, which could reduce machining scratches and other micro defects, and achieve “flexible polishing” on the bearing steel element surface. The studies indicated that high surface integrity of bearing steel element could be obtained by this new high-efficiency polishing method.