Precise Finishing Process And Experimental Research On Typical Hole

With the development of the equipment manufacturing industry, the application of the hole-type parts is more and more widely. The surface quality of parts has significant influence on the assembly precision and service life. As the common method of the precision machining, the grinding effect directly affects the performance and reliability of the hole. Magnetic abrasive finishing process is a new type of grinding process, the magnetic abrasive particles between magnet and workpiece will be magnetized in the presence of a magnetic field and arranged along the lines of magnetic force to form a flexible magnetic abrasive brush for pressing workpiece surface. The magnetic abrasive brush will scrape and squeeze the workpiece surface under the comprehensive action of magnetic force and friction to realize precision machining of the hole inner surface, when a relative motion between the magnetic abrasive brush and workpiece surface is provided.Based on the mechanism of magnetic abrasive finishing, this paper carried out a series of simulation and experimental research with H62 brass, SUS304 stainless steel,Al6061 and 45 steel four kinds of typical material circular hole and TC4 titanium material tapered hole. Analyzed the main factors and rules which affecting the magnetic abrasive finishing effect mainly by the indexes including surface roughness and surface morphology. The specific contents of this article include the following aspects:(1)Described the development status at home and abroad, the concept and characteristics of magnetic abrasive finishing method, proposed the main research content and purpose of this subject. Studied the force of magnetic abrasive particles in magnetic field, and established the micro removal model of magnetic abrasive finishing. The feasibility of magnetic abrasive finishing of the hole surface was proved in theory.(2)Developed the magnetic abrasive finishing experimental setup in terms of circular hole and taper hole, introduced the experimental equipment and material properties of test sample, and conducted the ANSYS numerical simulation analysis of magnetization of the magnetic pole and working gap between the magnetic pole and the workpiece, provided a theoretical basis for further experimental research.(3)According to the orthogonal experiment method designed multiple sets of experiments of circular hole, studied the finishing process parameters(magnetic pole speed, abrasive particle size and filling amount), slurry type, material properties influence the surface quality and rules. Carried on the summary and analysis theresults of the experiment, getting the trends of surface roughness and significant degree of the influence with different factors are got, combined the surface micro topography of the processed workpiece, and obtained relatively optimal combination of process parameters.(4)In order to further improve the finishing efficiency and finishing quality on titanium taper hole, the ultrasonic vibration is introduced based on the conventional magnetic abrasive finishing process. It can increase the instantaneous pulsating finishing pressure of the magnetic abrasive particles. The cutting edge of magnetic abrasive particles formed multi-directional cutting path under the comprehensive action of magnetic force, centrifugal force and vibratory force. The material removal rate of workpiece is higher than conventional magnetic abrasive finishing process, and the surface roughness is lower, the surface micro morphology is uniform, the shape accuracy is improved.