Sedimentations on high-precision surfaces of advanced materials by magnetorheological finishing

Magnetorheological finishing (MRF) is a computer controlled polishing (CCP) technique for high precision surfaces. The process uses a magnetorheological fluid which stiffens in a magnetic field and thus acts as the polishing tool. A standard MR fluid consists of magnetic carbonyl iron (CI) particles, nonmagnetic polishing abrasives and liquid. To delaying oxidation of the iron particles and avoiding agglomeration the liquid consists of water completed with stabilizers. For the material removal and smoothing of the surface mostly cerium oxide or diamond is used. The materials to be polished may tend toward to different sedimentations of the MR fluid on the machined surface. These sedimentations result from the machining and may develop a polishing layer with MR fluid components. At the University of Applied Sciences Deggendorf analysis of the machined surface are made by the scanning electronic microscope (SEM) to determine the sedimentations of the finishing. The results of the research display the influence for the surface properties due to developing polishing layer by magnetorheological finishing.