Flow Field Design And Process Technology Of Electrochemical Cutting Mortise Processing By Thin Hollow Cathode

With the rapid development of aerospace technology,higher requirements are put forward for material performance and complex cavity structure processing.As a new machining technique to improve processing efficiency,electrochemical cutting machine the parts with complex shape are directly frame processed from the profile or the simple blank.Thus,net forming or near net forming of Aerospace metal complex structures can be realized efficiently.Aiming at the problems of stray corrosion,uneven slit and short circuit caused by unstable flow of electrolyte in the gap of electrolytic machining,a technology scheme of active flow field control was presented,In order to improve the flow field characteristics and the localization of processing,Through the design and planning of the entry and exit path of electrolyte,the real-time control of the flow and pressure of electrolyte in the electrolytic processing area can be realized.The structure of mortise,which is widely used in aerospace field,is selected to study the flow field control by electrolytic cutting.The main contents of this paper include the following items:Firstly,the theoretical model of electrolytic cutting forming is established.By analyzing the mechanism of electrolytic cutting,the model of anode metal material removal is put forward.The key factors affecting the processing efficiency are obtained.Combined with the analysis of the flow field characteristics of the gap in electrolytic cutting,the relevant measures to improve the flow field are obtained.Secondly,the flow field design of electrolytic cutting process is carried out.The finite element method?FEM?is used to simulate and analyze the flow field of the gap between the positive flow mode and the reverse flow mode in the process of electrolytic cutting mortise.Compared with the flow field pressure and the flow rate of electrolyte in the gap between the two modes,the design of the reverse flow field is more advantageous and more conducive to the active guidance of the flow direction of electrolyte.Active control of continuous flow field provides theoretical support.Thirdly,the process scheme of active control of flow field in electrochemical cutting is designed:according to the technological characteristics of mortise structure electrochemical machining,the corresponding fixture is designed,and the feeding circuit of electrolyte reflux active guidance is realized;and the cathode structure of mortise structure processing tool matched with it is designed,and the cathode structure is optimized based on fluid-solid coupling simulation,which improves the cathode structure.Integral stiffness of pole structure.Finally,the process experiment of active control of flow field in electrochemical cutting process is carried out.The effects of electrolytes with different ratios of NaCl and NaNO₃ on the surface morphology of titanium alloy TC4,superalloy and high-temperature stainless steel are discussed through many experiments.The effects of processing voltage and feed speed on average seam width and surface roughness are systematically studied and analyzed.The influence of liquid temperature on cathode feed speed of tools proves the feasibility and efficiency of active flow field control technology in direct electrolytic cutting.