Mechanistic study on the enhancement of vibration-impact effect by high-concentration carbonyl iron MRF to improve SiCp/Al surface quality

In this study, to improve the surface quality of SiCp/Al using the vibrational magnetorheological compound polishing method, the mechanism behind the enhanced vibration-impact effect through the use of high-concentration carbonyl iron magnetorheological fluid (HCCI-MRF) was elucidated for the first time. The vibration-impact effect of abrasives on the stability of microstructures in MRF was analyzed to elucidate the mechanism behind the improved surface quality. A shear yield stress model based on triangular microstructures was proposed for HCCI-MRF to characterize its mechanical properties. Rheological tests were performed to validate the accuracy of the proposed yield stress model and to qualitatively analyze the effect of vibration on the dynamic properties of MRF. Furthermore, a material removal rate (MRR) model integrating vibration-impact force and MRF mechanical properties was developed to demonstrate how these factors collectively contribute to the enhanced MRR. When integrated with the polishing experiments on SiCp/Al, the HCCI-MRF transforms the vibration-impact effect into a beneficial factor, preserves the stability of microstructures, and thereby enhances polishing force, MRR, surface quality. Both HCCI-MRF and vibration-impact effect contribute to decreasing the step height of SiCp/Al, while the vibration-impact effect plays a more significant role than the HCCI-MRF. Therefore, elucidating the enhancement mechanism of the vibration-impact effect mediated by HCCI-MRF is critical to understanding the synergistic mechanism governing composite polishing.