Magneto-rheological finishing technique (MRFT) for enhanced surface finish in components fabricated through hybrid deformation machining (HDM) and conventional processes

Abstract

Hybrid Deformation Machining (HDM) is an advanced manufacturing technique that integrates subtractive machining and incremental forming to achieve precise monolithic shapes. It is widely used in the aerospace, medical, and energy industries, where high surface quality is critical. This study explores the integration of the Magneto-Rheological Finishing Technique (MRFT) with HDM to enhance surface quality. A customized magneto-rheological fluid (MRF) is employed for effective polishing. An AA6061-T6 aluminum alloy block was machined into 2 mm floor thickness circular pockets using turning and milling operations. These machined pockets then underwent incremental stretch forming to achieve the desired geometry. MR finishing was selectively applied after different fabrication stages, that is, post-machining and post-incremental forming. Two sets of components were fabricated under different machining conditions, that is, turning and milling. Each set comprises six samples based on surface roughness measurements after different experimental variations: (1) machined-circular-pocket, (2) machined-incrementally formed, (3) machined-incrementally formed-MR finished, (4) machined-MR finished, (5) machined-MR finished-incrementally formed, and (6) machined-MR finished-incrementally formed-MR finished. Given the presence of flat, vertical, and inclined surfaces, three distinct MR finishing tools were designed and developed. Results indicate that MR finishing significantly improves surface quality. The turned-MR_finished-incrementally formed-MR finished component exhibited a ~33% improvement in surface quality compared to the turned-incrementally formed component. Similarly, the milled-MR_finished-incrementally formed-MR finished component showed an ~18% improvement compared to the milled-incrementally formed component. These findings demonstrate the effectiveness of MRFT in enhancing surface quality, particularly for monolithic components fabricated through the HDM process, thereby advancing precision manufacturing.