Application and analysis of adiabatic blanking

• Applicants: Professor Dr.-Ing. A. Erman Tekkaya; Professor Dr.-Ing. Martin Franz-Xaver Wagner
• Subject Area: Primary Shaping and Reshaping Technology, Additive Manufacturing
• Term: from 2020 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 428780322

• Final Report Year: 2024

Final Report Abstract

In high-speed blanking, the resulting process heat does not dissipate and leads to a thermal softening of the material. This process characteristic allows higher surface quality than the conventional process. To date, there are no physically motivated approaches to distinguish this from the conventional process. The influence and interaction between strain rate and temperature development is also unclear. New characterization methods are being investigated in order to be able to map the interaction on the flow behavior as well. In addition, a new temperature-dependent failure model is used to numerically represent the increase in ductility. Several energy quantities (machine, kinetic, shear energy) are determined experimentally, from which an objective measure for the evaluation is derived. By means of an analytical model, the influence of the material properties and the process speed on the temperature development is shown, in order to derive a delimitation of the HGSS. The short process time (0.1 ms) limits real-time measurements, so that the estimation of the thermal softening is done post-mortem based on an instability criterion. While HGSS improves surface quality, effects on downstream deformation (‘edge crack sensitivity’) and deformation remain unexplored. Investigations address both resulting properties.

Publications

• Prediction of adiabatic blanking process properties with temperature dependent fracture criterion, International Conference on High Speed Forming - ICHSF
  F. Schmitz, T. Rakshit, M. Hahn, T. Clausmeyer & A. E. Tekkaya
  
• Modelling and analysis of adiabatic blanking of AHSS with different heat treatment, International Conference and Workshop on Numerical Simulation of 3D Sheet Metal Forming Processes - NUMISHEET, Toronto (CA). Konferenzvortrag
  F. Schmitz, B. Bohne, M. Hahn, T. Clausmeyer, M. Wagner & A. E. Tekkaya
  
• Strain-rate sensitive deformation behavior of a quenched and tempered C75S steel in a wide range of temperatures, FEMS Euromat, Frankfurt (DE). Konferenzvortrag
  B. Bohne & M. F.-X. Wagner
  
• Determination of energies in high-speed blanking. Journal of Manufacturing Processes, 124, 1554-1566.
  Schmitz, Fabian; Clausmeyer, Till; Hahn, Marlon & Tekkaya, A. Erman