Successful disputation by Lukas Schell!

The successful disputation of our former research assistant and senior engineer Lukas Schell took place in January. His dissertation is entitled “Development methodology for transparent model tests in sheet metal forming using the example of heat transfer coefficients and tribology”.

In his dissertation, Mr. Schell presents a development methodology for model tests that combines the V-model according to VDI 2206 with a field of tension consisting of three fundamental characteristics of model tests. The development methodology is exemplarily applied to the development of two model tests for the non-isothermal sheet metal forming of aluminum. Compared to the state of the art, the developed model tests differ in the areas of property validation and transparency, which facilitates the interpretation of the results and also the future design of related model tests.

The tribological model test is based on a strip drawing test and is capable of mapping various lubricant-specific phenomena and determining coefficients of friction as a function of the initial temperatures of the sheet and tool. The transparent representation of deviating results between the model and the real process is only made possible by the consistent validation of properties based on the development methodology. As part of the development of the IHTC model test, various methods for determining IHTCs (Initial Heat Transfer Coefficients) are analyzed experimentally and based on models. The results show that previous IHTC values from the literature underestimate the heat transfer between sheet metal and tool by up to 90 %. The IHTC model test essentially benefits from the consistent implementation of the modeling provided for in the development methodology and the analysis of the validation possibilities.

PtU would like to thank Mr. Schell for his many years of commitment and wishes him all the best and every success for his professional and private future.