P 1291 – Workpiece-side impact on and modelling of tribological conditions within hot stamping
The occurrence of friction and wear represents a current and pressing challenge in the hot stamping process, as the use of lubricants is not possible due to elevated process temperatures > 850 °C. The tribological conditions in the contact zone between the tool and workpiece are a critical component in the process, which has a significant influence on both the tool life and the quality of the final product. While the previous project P1228/19337 “Influence of tool-side tribological conditions on hot stamping” investigated the factors influencing the hot stamping process on the tool side, previous esearch work has shown that the coating used on the workpiece side has a significant influence on the friction and wear mechanisms that occur.
The objective of the research project is to determine functional correlations between austenitizing parameters and coating formation as well as the tribological application behavior of coating materials during press hardening. By understanding the interrelationships, measures will be determined which increase the overall lifetime of hot stamping tools and thus the economic efficiency of the process.
To achieve the research objective, two workpiece materials with different coatings were selected for the investigations in consultation with the industrial partners. In addition, different austenitization parameters and their influence on the resulting formation of the coating were analyzed. The results were used to identify significant parameters and investigate their influence on the friction and wear behavior based on the strip drawing test. The investigations have shown that the austenitizing parameters have no effect on the resulting friction behavior in the context of the laboratory tests. However, both the choice of workpiece material and its coating can have an influence on the tribological behavior. The results were consolidated in the form of a friction model and made available as a mathematical equation.
All research reports in german language only!
F. He, M.Sc. Prof. Dr.-Ing. habil. M. Merklein