Synthesis and Performance Evaluation of Magnetorheological Fluid for Continuous Flow Finishing Process

In this study, Magnetorheological (MR) finishing fluid samples have been synthesized and experiments have been conducted to investigate the rheological properties namely off-state viscosity and on-state yield stress of prepared samples. The compositions of the MR finishing fluid havebeen determined by using Taguchi based design of experiment approach. The MR properties have been characterized on a rheometer, using MR device accessory. Bingham Plastic, Casson fluid and Herschel Bulkley are the three fluid models utilized for the modelling of the fluid. The Hershel–Bulkley model has resulted as the most apposite model for fluid with the highest coefficient of regression (R² ) value i.e., 0.9049. Further, Technique for order of preference by similarity to ideal solution (TOPSIS) has also been utilized to establish the effect of its constituents on both the considered rheological properties. To determine the magnetic saturation of the developed MR finishing fluid, graphs between magnetic field strength and on-state yield stress have been plotted. Analysis of Variance (ANOVA) publicized the weight percentage of Fe powder as the most notable parameter, contributing 66.12% followed by the weight percentage of SiC abrasives with 8.09%. The MR finishing fluid samples have attained the highest yield stress at magnetic field intensity of around 0.7 Tesla, which is considered as the limiting value for the finishing process. The optimized fluid sample has been used for finishing 2 mm hole using an indigenously developed finishing process.