Theoretical and experimental investigations on magnetic abrasive finishing (MAF) for finishing of flat and cylindrical components for cryogenic applications

Magnetic Abrasive Finishing (MAF) can be employed for finishing of flat and cylindrical turboexpander components’ surfaces at nano-level. MAF can nano-finish surfaces to the order of 20 nm and better. Using the Design of Experiments (DoE) technique, experiments were carried out on an existing MAF setup. By mathematical modelling of the experimental data using regression technique, a correlation between the critical process parameters of the MAF process and final surface roughness, R_a, of the work surface has been developed. This regression model has been compared with a theoretical model for the MAF process from literature. Working gap between the work piece and the magnet, and Rotational speed of the work piece were observed as two of the most influential MAF process parameters. Both these parameters have optimum values (Gap = 1.25 mm, Speed = 800 RPM), at which the lowest R_a value was obtained for the existing MAF setup.