The Research On Ultrasonic Vibration Assisted Electrochemical Grinding GH3536

In recent years,with the rapid development of the aviation industry,the production units of various departments have increasingly demanded the performance of aerospace parts and their processed materials,requiring materials with high strength,good corrosion resistance and high temperature resistance,The processed parts have high surface processing quality and dimensional accuracy.Nickel-based superalloy GH3536 is a very typical one of the difficult-to-machine materials commonly used in the aerospace field.When traditional machining and special processing are used,there are often poor machining accuracy,poor surface integrity,serious wheel wear,large residual stress and remelting Problems such as layers,so this article proposes an efficient composite machining method using ultrasonic-assisted pulsed electrochemical grinding,that is,using an ultrasonic generator and a horn to convert the alternating current signal into mechanical vibration and introducing it into electrochemical grinding.Using the cavitation effect of ultrasonic vibration and the mass transfer effect of the liquid phase,it is ensured that the flow field is more stable during the electrochemical grinding process,and the electrochemical products and bubbles between the gaps between the poles can be quickly discharged.Compared with traditional mechanical grinding,electrochemical machining and electrochemical grinding,the surface machining quality and machining accuracy of GH3536 alloy small holes have been greatly improved.In this paper,ultrasonic vibration assisted electrochemical grinding process is used to efficiently process GH3536 holes,and the theoretical analysis and Experimental Research on material removal mechanism are carried out.The main research contents are as follows:(1)In this paper,the machining principle,the characteristics of machining range and the parameters affecting the process test of ultrasonic vibration assisted tube electrode electrochemical machining pre hole and ultrasonic assisted electrochemical grinding reaming are described.The electrochemical dissolution mechanism of GH3536 alloy was studied by using three electrode system and electrochemical workstation.The open circuit potential and polarization curves of GH3536 alloy in NaN03 solution and NaCl solution at different concentrations were measured.The current efficiency at each current density was measured in 10%NaN03 solution,which provided extremely important guidance for the analysis of the forming rules of electrochemical machining and the actual machining process.(2)In this paper,an experimental platform of ultrasonic vibration assisted electrochemical grinding is built,including the main body of the electrochemical grinding machine,power control system,ultrasonic vibration system,electrolyte circulation system,collection and monitoring system,tool electrode and clamping device.Through ANSYS,the stability analysis of the ultrasonic vibration of the ultrasonic motorized spindle is carried out,mainly including modal analysis and harmonic response analysis.The natural frequency of the vibration is measured on the basis of free vibration,and the response stress and displacement of the ultrasonic vibration are measured on the basis of modal analysis.(3)The mathematical model and simulation model of ultrasonic vibration assisted electrochemical grinding are established,and the dynamic grid technology is put forward.The electric field between the pre hole and the reamed hole in electrochemical machining of electrode in ultrasonic vibration assisted tube is simulated and analyzed by using the COMSOL multiphysics.The current density distribution diagram of workpiece surface and the transient evolution process of small hole forming are obtained.(4)Based on the pre hole of ultrasonic vibration assisted electrochemical machining of tube electrode,the experiment of expanding hole by ultrasonic vibration assisted electrochemical grinding was carried out.The influence of different parameters,such as pulse voltage,feed speed,grinding head speed and ultrasonic amplitude,on the average taper,surface roughness and surface shape of the hole was analyzed.The change of surface processing quality and processing accuracy by different process parameters was obtained Law.Four factors and three levels of orthogonal test method were used to optimize the hole expanding by ultrasonic electrochemical grinding.The most influential factor on the surface roughness and average taper of the hole was determined by range analysis method as the machining voltage.