Research On Lapping Technology Under Swing-Type Plane Lapping Mode For Ceramic Balls

Ceramic balls have excellent properties, they are widely used in high accuracy and speed machines, cars, racing, subway, motor, aviation engine, petroleum chemical machines, metallurgical machines and so on. But because ceramic balls are very hard and difficult to process, it can not to be processed in a high efficiency so far. Silicon nitride blank balls need to be removed 95% of processing allowance in rough lapping period, so improving the efficiency of rough lapping period can improve the whole machining efficiency largely.In the paper, a swing type plane lapping technology is proposed to process silicon nitride blank balls in rough lapping period. This technology can use solid abrasive in the machine to lap rigid blank balls, and can obtain a highly process efficiency. Besides, the technology can size the soft blank balls in the machine to further improve the efficiency. The two machining method can remove allowance quickly, cut the processing time. Besides, the rigid and soft silicon nitride blank balls are full sintering balls and pre-sintering balls respectively.The mainly research contents in this paper are as follows:1. Analyzed the principle and constitution of the swing type plane lapping device. The blank balls were drove by the rotation of the lower plate and the swing of the upper plate in the device, and the material was removed by the friction between blank balls and the lower plate. The device was composed of lapping plate, driving system, pressure system, swing mechanism and lapping fluid circulation system.2. Based on the kinematic analysis on blank balls, kinematical equations were established to found motion rule of blank balls. MATLAB software was used to analyze the relationship in the parameters in the equations, and the self-rotate angle was proved changing uniformly in the range of -?/2 and ?/2. ADAMS software was used to make model about the lapping course of the blank balls, simulated the lapping track on balls surface, and analyzed the pressure and rotate speed ratio in lapping on the distribute of the surface track.3. Two experiments were designed, and the research objects were the pre-sintered blank balls and the full sintered blank balls respectively, the diameter of pre-sintered blank balls were ?13mm and the diameter of full sintered blank balls were ?10mm. Designed and optimized the two processing parameters through single factor experiment method, and the two processing parameters were lapping pressure and rotate speed ratio. Based on the results, the pre-sintering blank balls were needed a small pressure and the full sintering blank balls were needed a large pressure. When the rotate speed ratio was 3.3, the roundness error was lest. The process to pre-sintering blank balls could achieve a higher efficiency than the process to full sintering blank balls.The process to ceramic blank balls by the swing type plane technology in this paper has a high material removal rate, solves the problem of hard process, and has a important significance in further using of silicon nitride balls.