Improving profile accuracy and surface quality of blisk by electrochemical machining with a micro inter-electrode gap  

作　　者：Jingtao WANG Zhengyang XU Di ZHU 

机构地区：[1]College of Mechanical and Electrical Engineering,Nanjing University of Aeronautics and Astronautics,Nanjing 210016,China

出　　处：《Chinese Journal of Aeronautics》2023年第4期523-537,共15页中国航空学报（英文版）

基　　金：sponsored by the National Science and Tech-nology Major Project(Grant No.2017-VII-0004-0097);National Natural Science Foundation of China for Creative Research Groups(Grant No.51921003);the Postgraduate Research&Practice Innovation Program of Jiangsu Province(Grant No.KYCX21_0191).

摘　　要：Electrochemical machining(ECM)has emerged as an important option for manufacturing the blisk.The inter-electrode gap(IEG)distribution is an essential parameter for the blisk precise shap-ing process in ECM,as it affects the process stability,profile accuracy and surface quality.Larger IEG leads to a poor localization effect and has an adverse influence on the machining accuracy and surface quality of blisk.To achieve micro-IEG(<50 lm)blisk finishing machining,this work puts forward a novel variable-parameters blisk ECM strategy based on the synchronous coupling mode of micro-vibration amplitude and small pulse duration.The modelling and simulation of the blisk micro-IEG machining have been carried out.Exploratory experiments of variable-parameters blisk ECM were car-ried out.The results illustrated that the IEG width reduced with the progress of variable parameter pro-cess.The IEG width of the blade’s concave part and convex part could be successfully controlled to within 30 lm and 21 lm,respectively.The profile deviation for the blade’s concave surface and convex surface are 49 lm and 35 lm,while the surface roughness reaches R_(a)=0.149 lm and R_(a)=0.196 lm,respectively.The profile accuracy of the blisk leading/trailing edges was limited to within 91 lm.Com-pared with the currently-established process,the profile accuracy of the blade’s concave and convex profiles was improved by 50.5%and 53.3%,respectively.The surface quality was improved by 53.2%and 50.9%,respectively.Additionally,the machined surface was covered with small corrosion pits and weak attacks of the grain boundary due to selective dissolution.Some electrolytic products were dispersed on the machined surface,and their components were mainly composed of the carbide and oxide products of Ti and Nb elements.The results indicate that the variable-parameters strategy is effective for achieving a tiny IEG in blisk ECM,which can be used in engineering practice.

关 键 词：Electrochemical machining BLISK IEG Machining quality Surface quality 

分 类 号：V263[航空宇航科学与技术—航空宇航制造工程]