Development of a numerical compensation framework for geometrical deviations in bulk metal forming exploiting a surrogate model and computed compatible stresses

authored by: Lorenzo Scandola, Christoph Büdenbender, Michael Till, Daniel Maier, Michael Ott, Bernd-Arno Behrens, Wolfram Volk
Abstract: The optimal design of the tools in bulk metal forming is a crucial task in the early design phase and greatly affects the final accuracy of the parts. The process of tool geometry assessment is resource- and time-consuming, as it consists of experience-based procedures. In this paper, a compensation method is developed with the aim to reduce geometrical deviations in hot forged parts. In order to simplify the transition process between the discrete finite-element (FE) mesh and the computer-aided-design (CAD) geometry, a strategy featuring an equivalent surrogate model is proposed. The deviations are evaluated on a reduced set of reference points on the nominal geometry and transferred to the FE nodes. The compensation approach represents a modification of the displacement-compatible spring-forward method (DC-SF), which consists of two elastic FE analyses. The compatible stress originating the deviations is estimated and subsequently applied to the original nominal geometry. After stress relaxation, an updated nominal geometry of the part is obtained, whose surfaces represent the compensated tools. The compensation method is verified by means of finite element simulations and the robustness of the algorithm is demonstrated with an additional test geometry. Finally, the compensation strategy is validated experimentally.
Organisation(s): Institute of Metal Forming and Metal Forming Machines
External Organisation(s): Technical University of Munich (TUM)
Type: Article
Journal: International Journal of Material Forming
Volume: 14
Pages: 901-916
No. of pages: 16
ISSN: 1960-6206
Publication date: 09.2021
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: General Materials Science
Electronic version(s): https://doi.org/10.1007/s12289-020-01603-7 (Access: Open)
: Details in the research portal "Research@Leibniz University"

BibTeX

@article{ad1693448bfa486787615a78e691a7a3,
title = "Development of a numerical compensation framework for geometrical deviations in bulk metal forming exploiting a surrogate model and computed compatible stresses",
abstract = "The optimal design of the tools in bulk metal forming is a crucial task in the early design phase and greatly affects the final accuracy of the parts. The process of tool geometry assessment is resource- and time-consuming, as it consists of experience-based procedures. In this paper, a compensation method is developed with the aim to reduce geometrical deviations in hot forged parts. In order to simplify the transition process between the discrete finite-element (FE) mesh and the computer-aided-design (CAD) geometry, a strategy featuring an equivalent surrogate model is proposed. The deviations are evaluated on a reduced set of reference points on the nominal geometry and transferred to the FE nodes. The compensation approach represents a modification of the displacement-compatible spring-forward method (DC-SF), which consists of two elastic FE analyses. The compatible stress originating the deviations is estimated and subsequently applied to the original nominal geometry. After stress relaxation, an updated nominal geometry of the part is obtained, whose surfaces represent the compensated tools. The compensation method is verified by means of finite element simulations and the robustness of the algorithm is demonstrated with an additional test geometry. Finally, the compensation strategy is validated experimentally.",
keywords = "Bulk metal forming, Compatible stresses, Compensation, Geometrical deviations, Surrogate model, Tool design",
author = "Lorenzo Scandola and Christoph B{\"u}denbender and Michael Till and Daniel Maier and Michael Ott and Bernd-Arno Behrens and Wolfram Volk",
note = "Funding Information: The authors would like to thank the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) for financial support, provided under the grant numbers VO 1487/26 − 1. Open Access funding enabled and organized by Projekt DEAL. ",
year = "2021",
month = sep,
doi = "10.1007/s12289-020-01603-7",
language = "English",
volume = "14",
pages = "901--916",
journal = "International Journal of Material Forming",
issn = "1960-6206",
publisher = "Springer Paris",
number = "5",
}