Nanofinishing of silicon nitride workpieces using magnetorheological abrasive flow finishing

Magnetorheological Abrasive Flow Finishing (MRAFF) process was developed for deterministic finishing of internal and external surfaces by extruding magnetically stiffened magnetorheological abrasive polishing fluid. Silicon nitride is a brittle and hard, difficult-to-machine ceramic. Obtaining final surface finish in nanometer range and defect free surface is a challenge for manufacturing scientists. The finishing of silicon nitride workpieces was done using boron carbide, silicon carbide and diamond. The effectiveness of different abrasives was investigated and surface topography was observed under atomic force microscope.