Model-based prediction of the rim zone after electrical discharge machining of steels - MoVoRa

• Applicant: Professor Dr.-Ing. Thomas Bergs
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 560539728

Electrical Discharge Machining (EDM) is steadily gaining relevance in the manufacturing of components with high aspect ratios, complex geometries, and high hardness due to its non-contact working principle. As demands on the materials used (higher strengths and longer lifespans) increase, along with the necessity to reduce costs, new approaches are required to enable a function-oriented process control. In this context, model-based prediction of the resulting surface integrity and its properties based on microstructure in relation to the underlying technology is an indispensable step. Within the scope of this research project, simulation models are to be developed and validated, capable of predicting the microstructure in both the re-solidified layer and the heat-affected zone. Since relatively little is known about the re-solidified layer to date, it must be fully characterized in the first step to gain a better understanding of the formation mechanisms and influence on the re-solidified layer. Additionally, these experimental investigations serve as both the necessary basis for modeling the phases within the simulation models and the foundation for the final validation of the simulations. Subsequently, the resulting temperature field for the continuous EDM process is to be determined through finite element method (FEM) simulation. The thereby determined thermal stress during EDM forms the fundamental condition for the microstructure simulation models, which are intended to be established in the last step of the research project. This involves simulating both the liquid-solid phase transformation of the re-solidified layer and the solid-solid phase transformation within the heat-affected zone. Upon successful completion of the research project, it becomes possible to predict the temperature field and the resulting microstructure (grain size, phase distribution, etc.) in the workpiece material after EDM.

• DFG Programme: Research Grants