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Статья. Опубликована в журнале "World Academy of Science, Engineering and Technology". – 2012. – No. 61 – P. 499-503.
Название на русском языке: Оценка эффективности улучшенного инструмента в виде шаровой головки для магнитореологических отделочных процессов.Аннотация к статье на английском языке: A novel nanofinishing process using improved ball end magnetorheological (MR) finishing tool was developed for finishing of flat as well as 3D surfaces of ferromagnetic and non ferromagnetic workpieces. In this process a magnetically controlled ball end of smart MR polishing fluid is generated at the tip surface of the tool which is used as a finishing medium and it is guided to follow the surface to be finished through computer controlled 3-axes motion controller. The experiments were performed on ferromagnetic workpiece surface in the developed MR finishing setup to study the effect of finishing time on final surface roughness. The performance of present finishing process on final finished surface roughness was studied. The surface morphology was observed under scanning electron microscopy and atomic force microscope. The final surface finish was obtained as low as 19.7 nm from the initial surface roughness of 142.9 nm. The outcome of newly developed finishing process can be found useful in its applications in aerospace, automotive, dies and molds manufacturing industries, semiconductor and optics machining etc.
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World Academy of Science, Engineering and Technology 61 2012
Performance Evaluation of Improved Ball End Magnetorheological Finishing Process Anant Kumar Singh, Sunil Jha, Pulak M. Pandey technology. In general, MR polishing fluids consist of magnetic carbonyl iron powder (CIP), polishing abrasives, carrier fluid, and stabilizers. Properties such as plasticity, elasticity, and apparent viscosity change with the application of magnetic field. MRF is used to precision finishing of concave, convex, flat and aspherical optical components [9]. Recently, authors have designed and developed a nanofinishing process using ball end MR finishing tool which was already reported [10].This is used for finishing of flat as well as 3D surfaces of ferromagnetic and non ferromagnetic materials. The MR finishing tool was comprised of concentrically placed inner core, electromagnet coil and outer core and it rotates as a whole during the finishing operation. In this design there were no any cooling coils applied over the outer surface of electromagnet coil due to its rotational motion. The improved ball end magnetorheological finishing tool has been used for the present MR finishing process (Fig.1). It comprises of a central rotating core, stationary electromagnet coil and further copper cooling coils integrated over the outer surface of the stationary electromagnet coil to cool it continuously. The cooling medium is supplied by low temperature bath. The two ball bearings, timing pulley and rotary valve are mounted on the MR finishing tool. A magnetically generated stiffened ball end of MRP-fluid at the tip surface of tool was used as a finishing medium. The main advantage of the tool design is in flow of intermittent pressurized MRP-fluid through centre of the tool core and gets stiffened controlled ball end shape of MRP-fluid at the tip of the tool. The flow of MRP- fluid at the tip of tool is intermittent during the finish operation. Whenever MRP- fluid is required to be conditioned after certain period of finishing operation then only it flows at the tip surface of the tool. Otherwise the already formed stiffen ball end of MRP-fluid is used continuously for finishing operation. The conditioning of MRP-fluid at the tip surface of the tool can be done by replenishing fresh MRP-fluid. The MR finishing tool tip with stiffened ball end of MRPfluid can be easily made reach