To improve the finishing efficiency of the magnetic abrasive finishing (MAF) process and achieve high-quality surface finishing, the magnetic abrasive finishing combined with electrolytic (EMAF) process is proposed. This is a novel finishing process in which the electrolytic process is used to quickly flatten the surface and the MAF process is used to remove the passive film generated by the electrolytic process and further finish the surface of the workpiece. In this study, to improve the surface uniformity and finishing efficiency for finishing aluminum alloy A5052, a pulse voltage was used for the EMAF process. The machining characteristics of the comparison of DC voltage and pulse voltage and the effects of frequency and duty ratio were investigated. The best experimental conditions were pulse voltage of U_RMS 4 V, 1 Hz, and duty ratio of 25%, with which the surface roughness could reach Ra 16 nm.

The shape accuracy of the screw rotor is critical in controlling the performance of the single-screw compressor mechanism. Dedicated machine tools, therefore, have been used for machining of the screw rotors. In manufacturing of compressors, higher efficiency and durability have recently been required in screw machining on 5-axis machining centers as general purpose machine tools. As the groove of the screw rotor becomes deeper in the center portion, the interference of the tool and the workpiece should be considered in tool path control. However, commercially available Computer-aided manufacturing(CAM) sometimes cannot be applied to generate the continuous motion of the tool vector. This study presents a strategy for controlling tool axis inclination to finish the side blades of the screw rotors by end mills. A machining error compensation approach was also developed to minimize the geometrical error from the specified shape with the error analysis model. In actual cutting of a large screw rotor, the machining time was reduced to 1/10 compared to ball end milling.

It is difficult to predict the amount of wear in the polishing process of a spherical glass lens because the relative velocity distribution and contact pressure distribution of the polished surface change from moment to moment. This study was performed to determine whether the amount of wear could be predicted by Preston’s equation based on the relative velocity and contact pressure of the polished surface calculated by the finite element method. Furthermore, the grindstone curvature obtained by experiment showed a strong correlation with that obtained in a simulation using the same experimental design. The grindstone curvature after machining was also found to increase in proportion to the magnitude of the load.