Cathodic Modification, Numerical Simulation and Experimental Investigation on Electrochemical Machining for the Small Inner-walled Ring Groove

• Published in: International journal of electrochemical science Vol. 15; no. 4; pp. 3453 - 3468
• Main Authors: Ai, Haihong, Yan, Zhenghu, Jiang, Xinguang, Cheng, Peiyong, Tian, Hao, Hu, Yanwei, Zhang, Changfu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.04.2020
• Subjects: Cathode modification; Electrochemical machining; Experimental investigation; Numerical simulation; Small inner-walled ring groove; Cathode modification; Electrochemical machining; Numerical simulation; Small inner-walled ring groove; Experimental investigation
• ISSN: 1452-3981; 1452-3981
• DOI: 10.20964/2020.02.56

Some important magnetic conductors, pneumatic valves and hydraulic valves made of corrosion-resistant alloy Cr16Fe (1J116) are often applied in harsh environments. However, it is very challenging to machine the inner-walledring grooves that broadly exist in these workpieces. Electrochemical machining (ECM) is regarded as an ideal manufacturing technology to machine this kind of structure without residual stress, metamorphic layers or microcracks. However, the inner-walledring grooves machined with ECM with the typical cylindrical cathode are shaped like a little drum and are not flat at the bottom. In this paper, a working-surface curvature cathodic modification and numerical simulation method is proposed to solve thisproblem. First, the working surface of the cathode is modified into an inward curved surface and is used in the flow field simulation model in which the k-ɛequation is employed. Then, the coupling analysis of the flow field and the electric field is carried out with COMSOL Multiphysics. The simulation results show that the machining quality of the inner-walledring groove isimproved with the modified cathode because the flow field distributionsand the electric field distributionsin the machining gap aremore uniform than before. Finally, verification experiments with the modified cathode are conducted. The experimental results show that the machined inner-walledring groove is of good quality, and the bottom of the groove is flat. The experimental results agree with the simulation results. This study is meaningful to provide a probable solution to improve the machining quality of the inner-walledstructure workpieces without residual stress, metamorphic layers or microcracks.