Research On The Process Of Rotary Ultrasonic Grinding Machining For Si₃N₄Ceramics

Si₃N₄ceramics material is widely applied in aerospace, chemical equipment, engine,military equipment, and other domains for excellent physical and chemical properties.However, because of its high hardness and high brittleness, processing efficiency of thetraditional processing method is generally low, and various types of surface or the sub-surfacedamage were generated in machining process of ceramic components, thus leading to thedecrease of strength of ceramic components. Si₃N₄ceramics components are limited to beused more widely because of high processing cost and difficult to control processing surfacedamage layer.Rotary ultrasonic grinding technology was applied in machining process of Si₃N₄ceramics in the paper. Based on elastic-plastic mechanics and indentation fracture mechanics,rotary ultrasonic grinding of Si₃N₄ceramics mechanism was analyzed; Processing mechanismwas simulated and verified through the module XFEM of finite element software ofABAQUS; The mathematical model between material removal rate（MRR） and the processparameters of Si₃N₄ceramics in rotary ultrasonic grinding machining was established and wasproved to be correct by experiments; Finally, the research above was applied in the practicalprocessing technic, with a single leaf Si₃N₄ceramics processing as an example, and guidingthe rotary ultrasonic grinding process of Si₃N₄ceramics.From the research above,3D stress field was analyzed in rotary ultrasonic grindingmachining of Si₃N₄ceramics. There were radial cracks, medium cracks and lateral cracks. Theemerge place, the requirement of grow and balance, the size of cracks were confirmedmeanwhile. The material removal of grinding and the material removal of ultrasonic vibrateare existent in process of machining, the two material removal patterns which take up of totalmaterial removal rate are not fixed with different processing parameters. The bigger theprocessing parameters, the more the material removal rate of ultrasonic vibrate. At the sametime, it not only can improve the processing efficiency and reduce cutting force, but also canimprove the quality of parts with rotary ultrasonic grinding machining of Si₃N₄ceramics.