Review of magnetic-assisted single-point diamond turning for ultra-high-precision optical component manufacturing

Single-point diamond turning (SPDT) is an emerging ultra-precision machining technology for use in advanced manufacturing of optical components. By using SPDT, critical components with optical surface roughness down to 1 nm could be manufactured. However, various factors can negatively influence the outcome of this state-of-the-art technology and affect the quality of the optical surface generation. Recently, the application of non-conventional machining techniques during the SPDT process has been emerging. Various technologies, based on different energy sources, have been developed and used for improving the optical surface generation mechanisms, process parameters, and turning conditions. One of the emerging techniques is based on the manipulation of a magnetic field around the cutting zone during diamond turning. Applying a magnetic field around the cutting zone during SPDT has shown promising results in terms of improving the quality of optical surface generation as well as machining variables, including tool wear, passive vibrations, and thermal conductivity of the workpiece material. In addition, by applying a magnetic field during the SPDT procedure, diamond turning of hard-to-cut materials, such as titanium alloys, in a dry machining condition becomes possible. The purpose of this review paper is to investigate the influence of a magnetic assistance technique on the outcome of the SPDT process. Magnetic-assisted SPDT is an emerging technique, and its constructive and destructive effects on SPDT process are not fully understood. Therefore, more research and investigations need to be done for fully comprehending these effects for enabling optimum SPDT behaviors that will result in the best possible process outcome in terms of optical surface generation.