Research On The Design And Machining Mechanism Of Two-Dimensional Ultrasonic Grinding Device

In recent years,the demand for precision processing of biomaterials has been increasing continuously.With its high strength,high hardness,good biocompatibility and excellent corrosion resistance,biomaterials have been widely used in the preparation of biological implants.At the same time,biomaterials are also typical difficult-to-process materials,which bring severe-challenges to precision processing.The two-dimensional ultrasonic vibration-assisted machining technology is an effective method for precision machining of difficult-to-process materials,that is especially advantageous for the ability of reducing the cut force and the temperature in the processing area due to its characteristics of complete separation.Therefore,a two-dimensional ultrasonic grinding device was designed and the design validity was verified through ultrasonic system testing.Then the two-dimensional ultrasonic grinding mechanism was studied,the abrasive movement characteristics of two-dimensional ultrasonic grinding was analyzed,and a two-dimensional ultrasonic grinding machining mechanism model was established,combining with ultrasonic machining experiments at different angles,which revealed the influence of processing the biological materials by two-dimensional ultrasonic grinding processing on the processing quality and the material surface modification.This article was conducted through the theoretical calculation and finite element simulation and mathematical model and process experiments,the main content of the research are as follows:(1)A two-dimensional ultrasonic vibration device was designed,which is composed of piezoelectric ceramic rings,asymmetric amplitude transformer and ultrasonic generator.The overall sizes of the device were designed by analytic theory and were optimized by finite element analysis.Impedance analysis and amplitude measurement experiments were applied to verify the performance of the two-dimensional ultrasonic device.(2)The kinematic characteristics of two-dimensional ultrasonic grinding was analyzed,and the effect of rotating machining angles in different spatial planes was studied,then the mechanism model of vertical plane and horizontal plane were established respectively.In the model,the variation of machining angle is introduced to reveal the influence of machining angle on material precision machining.(3)The two-dimensional ultrasonic grinding experiments were conducted to investigate the effect of the improvement of machining quality compare to the traditional processing methods and the relationship between machining factors were studied.The effects of different processing angles on the surface quality of biomaterials were also investigated.The rationality of the model was verified by the result of the statistical experiments.Then,the wettability experiments were carried out on processed biomaterials to verify the hydrophilic and hydrophobic properties of materials,and to study the surface modification ability of biomaterials after two-dimensional ultrasonic grinding.