Process-integrated measuring and control system for the determination and reliable generation of functionally relevant properties in surface edge zones during BTA deep-hole-drilling

• Applicants: Professor Dr.-Ing. Dirk Biermann; Professor Dr.-Ing. Frank Walther; Professor Dr.-Ing. Andreas Zabel
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering ; Mechanical Properties of Metallic Materials and their Microstructural Origins
• Term: since 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 401539425

Machining processes influence the surface layer of a component, which in turn determines its properties under operating loads. Therefore, it is desirable to know the state of the surface layer in metallic materials caused by the manufacturing process and, in addition, to control it specifically in order to produce an improved component service life or reliability. This is to be achieved within the project for the BTA deep hole drilling process. In the second phase of this research project, it is therefore planned, to develop a micromagnetic sensor system based on the analysis of Barkhausen noise and to implement it in the BTA drilling head. The qualification and upgrading of the measurement method were successfully carried out in the first phase. By combining the sensor technology with a regression model, which is based among other things on the process knowledge from the first phase, in a soft sensor, a robust process control is being developed and tested. This process control allows the adjustment of the surface integrity in bore walls in a reproducible manner. For this purpose, influencing and disturbance variables that occur in-process are to be analysed and taken into account in the control. The regression model is based on experimentally obtained data as well as on data resulting from 2D- and 3D- FEM-based as well as on analytical simulations. Furthermore, the specifically adjusted functional properties of the controlled deep holes are analysed in quasi-static and cyclic investigations. For this purpose, it is planned to record the material reactions in the surface layer depending on the stress and number of load cycles in order to enable a mechanism-oriented characterisation of the residual stress and fatigue behaviour of the controlled manufactured test specimens.

• DFG Programme: Priority Programmes
• Subproject of: SPP 2086: Surface Conditioning in Machining Processes