DEVELOPMENT AND SYNTHESIZATION OF MRP FLUID AND MR FINISHING

Abstract

The project is focused on the development and characterization of magnetic abrasive particles (MAPs) using solid phase sintering method. The Plain iron powder of 300 mesh size with 20 Volume% and 25 volume% SiC abrasives of 3000 mesh size have been mixed uniformly in the ball mill. The pellets of 5 gm each have been prepared at 8 ton pressure using cylindrical die with dimension 7 mm diameter and 50 mm length. After preparation of all pellets, the pellets were sintered in the tubular furnace in the inert atmosphere of argon at 10000C in a proper sintering cycle using solid phase sintering method. After sintering, the sintered pellets were crushed in ball mill to obtain the required magnetic abrasive particles. The particle characterization has been done on scanning electron microscope to understand the morphology of the particles and different elemental composition exist. The magnetorheological polishing fluid has been synthesized with 45 volume% magnetic abrasive particles (MAPs) and 55 volume% base fluid. Another sample is prepared with 20 volume% plain iron powder, 25 volume% silicon carbide abrasives of 3000 mesh size and 55 volume% base fluid. After synthesization of MRP fluid, the experiments have been conducted on ball end magnetorheological finishing (BEMRF) tool. In magnetorheological finishing, the finishing is carried out in controlled atmosphere by controlling the applied magnetic field. The initial surface roughness before the experiments and final surface roughness after conducting the experiments has been measured with Talysurf using 4 mm data length and 0.25 mm cut off length. Then percentage reduction in surface roughnes (%ΔRa) has been calculated and compared with %ΔRa obtained by conducting the experiments with unbonded magnetic abrasive based MRP fluid and found better results.