Research On Evaluation Method Of Properties And Its Application For High Precision Ceramic Balls

With the rapid development of modern mechanical industry, ceramic ball bearings, as a foundation parts or components for machinery, are widely used in the fields of aerospace, precision machinery, national de fense science and technology, etc. Therefore, the demand of the number and the requirements of the quality for high precision ceramic rolling elements are more and more critical. It’s necessary to establish a perfect and effective properties evaluation system for high precision ceramic ball.For further study on the performance of the high accuracy ceramic ball e valuation method, the silicon nitride ceramic balls are chosen as the research object. Mainly in aspects of the material properties, geometric acc uracy and surface quality, further study about the quality detection method, friction and wear properties, the relationship analysis between processing and quality of the sphere are made.In terms of detection methods of ceramic balls, the detection of vibration values are made. The ball vibration measuring instrument(BVT-1A) is used for the experimental research. According to the results, preliminary rules for G5 grade silicon nitride ceramic balls of Φ 4.763 that low- frequency vibration value is not mo re than 13 um/s, high- frequency vibration value is not more than 16 um/s; When surface is defected, the vibration value will be abnormal. Meanwhile, we found that waviness mainly affects the high frequency vibration value, roundness mainly affects low frequency vibration value, and the influence of roughness value is negligible. It is verified that quickly known about the surface geometry quality of ceramic ball has feasibility through the vibration value of frequency division measurement.In terms of friction and wear properties of ceramic ball, the friction source of ball bearing and its failure modes, high precision ball grinding technology was introduced. In addition, the kinematics analysis on double rotation grinding technique was taken as an example. Referring to four ball method, the way of single factor experiment was used to analysis the influence of pressure, rotational speed, abrasive particle size and concentration on the processing of ceramic ball friction coefficient. As a result, we found that there exist some suitable processing parameters under certain conditions.In order to understand the impact of process technology on surface quality of ceramic ball, the influence of grinding media and grinding parameters on surface quality during processing was studied. Then, the types of surface defects are introduced, and also is the further exploration about the impacts of surface defect on its bearing failure, which proves the importance of surface quality to ceramic ball bearing.