Electrochemical wire cutting with axial high-pressure flushing and internally flushed tube tools

• Applicant: Professor Dr.-Ing. Thomas Bergs
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering ; Joining and Separation Technology ; Production Systems, Operations Management, Quality Management and Factory Planning
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 423318338

The manufacturing process of electrochemical cutting with a wire electrode (Wire-ECM) offers high potential, with a wide range of applications. However, the successful implementation of the process has so far been hindered by an effective flushing strategy of the cutting kerf. The dominant process influencing factors for ECM cutting can already be derived from the results of the initial project phase. Furthermore, the use of axial pressure flushing and structured wire tools has significantly increased the cutting rate. However, the achievable material removal rates are not competitive yet, and the process is characterized by sporadic instabilities. Therefore, in this follow-up project, the approach of axial flushing with increasing flushing pressures will be further pursued. Additionally, the use of internally flushed tools appears promising for specifically improving electrolyte exchange in the critical area of the frontal working gap. The research hypothesis of the project is as follows: Axial high-pressure flushing and the use of internally flushed tools effectively improve flushing in the critical area of the working gap, resulting in a significant increase in cutting rate and process stability. The established approach of numerical analysis combined with subsequent empirical investigations will be continued. Initially, complex fluid flow will be analyzed using numerical models, and a process window for axial high-pressure flushing will be derived. Furthermore, the effect of internal flushing through the tool on electrolyte movement in the working gap will be investigated, and flow- and structurally optimized tube tools will be designed and manufactured. The empirical investigations will follow the numerical analyses, validating the simulation results and investigating the possibilities and limitations of flushing concepts. Based on the numerical and empirical studies, the process model developed in the initial research project will be expanded to include results from high-pressure flushing and the application of internally flushed tools. Additionally, empirical investigations on the machining of conical cutting paths and the machinability of a relevant steel material, as well as workpiece damage due to a short circuit in wire-ECM will be conducted.

• DFG Programme: Research Grants