Study On The Effect Of Vertical Ultrasonic Vibration Of Workpiece On The Gap Flow Field In EDM

Ultrasonic assisted EDM is a composite machining method combining the advantages of ultrasonic machining and electrical discharge machining.Ultrasonic vibration will affect the movement of the gap flow field and the expulsion of the particle.The purpose of this study is to explore the influence of the vertical ultrasonic vibration on the motion of the gap flow field of different discharge gap,different electrode diameter and different machining depth,and to analyze the effect of flow field on the machining parameters of EDM.Firstly,the influence of vertical ultrasonic vibration of workpiece on EDM,processing fluid and chip discharge is analyzed theoretically.Through theoretical analysis,it is found that the vertical ultrasonic vibration of the workpiece can increase the probability of EDM discharge,expand the pressure range of the EDM fluid,and make the pressure of the machining gap flow in the direction of X,Y and Z,which will be beneficial to the steady and continuous processing of the electric spark.Secondly,a set of workpiece vertical ultrasonic vibration device is designed to be installed on the conventional EDM machine.The best workpiece size can match with the ultrasonic resonance system was gain based on the modal simulation of ANSYS,and the designed ultrasonic vibration device is installed on the EDM450/60 NC electric spark CNC machine for debugging and checking.Thirdly,the Fluent software is used to simulate the vertical ultrasonic vibration EDM flow field of the workpiece with the gap of 40 ?m,55 ?m,65 ?m and 75 ?m,and the corresponding conventional EDM and ultrasonic EDM experiments were carried out.It is found that the reduction of discharge gap will increase the flow velocity and pressure range of the gap flow field and shorten the expulsion time of the particle.The vertical ultrasonicvibration of the workpiece can improve the machining efficiency and machining quality of the EDM,but the excessive flow velocity and the pressure change range will reduce this lifting effect.Finally,the effects of ultrasonic vibration on the flow velocity,pressure and the discharge of the particle in the gap between different electrode diameters and different machining depths are analyzed,and the corresponding conventional EDM and ultrasonic EDM experiments are carried out.The results show that there is a more obvious area effect and depth effect in the process of conventional EDM,and the reciprocating cycle caused by the workpiece with vertical ultrasonic vibration can effectively suppress the area effect and depth effect,improve the machining speed and machining precision of the EDM,and also increase the loss of the electrode and the loss of the electrode.The size error of the small hole after processing.