Magnetorheological polishing fluid to investigate wettability's impact on super finishing of bio-material

Abstract

It is necessary to develop an ultra-smooth surface finish for biomedical implants to enhance biocompatibility and reduce wear. Zirconium (Zr) alloys, which are known to have excellent corrosion resistance and biocompatibility, are promising materials for use in the medical field. However, achieving a higher surface finish on these hard-to-turn alloys is a significant challenge. In this novel study, a magnetic field-assisted finishing (MFAF) process was employed to advance the superfinishing of bio-zirconium (Bio-Zr) alloys, with particular focus on wettability, which varies because of alterations in the composition of magnetorheological polishing fluid (MRPF) but with constant abrasive particle and carbonyl iron particle (CIPs) levels. These modifications resulted in different MR fluids that had a significant impact on the quality of the surface finish. The experiments were conducted while keeping the other parameters unchanged and adjusting the MR fluid compositions only to determine their influence on surface roughness, finishing quality, and wettability. Surface roughness (Ra) and texture were measured on the superfinished surface with the following methods, namely non-contact three-dimensional surface profilometry, SEM, and AFM. Furthermore, contact angle measurements were performed to analyze the wettability of the superfinished interface, which showed that the roughness of the surface (Ra) can be minimized to the nanoscale, with a minimum of 44 and 61 nm under the optimum condition when the initial roughness is 475 and 460 nm, respectively. The present study brings to the possibility of the MFAF process in regulating the surface properties to enhance performance in biomedical applications.