Servicenavigation

Project Details

Back

Projekt Print View

Single-step production of metal-polymer-metal sandwich structures with a fiber-reinforced core: experiment, modeling and simulation

Subject Area Polymeric and Biogenic Materials and Derived Composites
Plastics Engineering
Mechanics
Metallurgical, Thermal and Thermomechanical Treatment of Materials
Production Automation and Assembly Technology
Primary Shaping and Reshaping Technology, Additive Manufacturing
Term from 2017 to 2023
Project identifier Deutsche Forschungsgemeinschaft (DFG) - Project number 330043166
 
Final Report Year 2024

Final Report Abstract

In this project, a single-stage forming and joining process of thermoplastic fibre-reinforced plasticmetal hybrid materials (FML) was developed, tested, characterized and simulated. To this end, investigations were carried out in three scientific directions: (1) tool and process development of a variothermal (VT) manufacturing process, (2) basic material characterization for material and process modeling and simulation, and (3) characterization of the forming behavior of such hybrid materials according to a single-stage process and – as a reference and benchmark – the production of FML semi-finished products in a two-stage process semi-finished product-component production. The aim of the single-stage process was to consolidate the individual layers, which only have a very limited forming potential at room temperature due to the glass fiber-reinforced (polyamide) PA core layer, and to form them into complex, three-dimensional components in a single process stage in the deep-drawing process. This approach offers advantages in terms of optimized material usage and the recyclability of the materials used, particularly with regard to the glass fibre-reinforced core material. Process windows for defect-free component production were determined for the different material combinations and geometries and shown in forming limit curves. This requires forming close to the melting range of the PA used in order to enable at least moderate forming of the glass fiber-reinforced core. In addition to the time-consuming construction and test phase of the VT tool, a tool was developed for the production of test samples that was adjustable in terms of temperature and pressure and could therefore reproduce the conditions of the VT tool in the press. Furthermore, the existing sheet metal testing machine was converted for basic tests on deep drawing and equipped with a controlled heated and coolable punch so that the deep drawing process could be reproduced in the VT tool and, thus, characteristic values could be determined under these conditions. As expected, the production of components with large drawing depths is not possible, but contours, e.g. hat profiles, which are produced by a pure bending process in the press, can be produced without any problems. Thus, the use of such profiles as crash box elements has been successfully demonstrated. The constitutive equations required for the process simulation were developed or taken from the literature and the associated material parameters were determined on the basis of special tests in such a way that their quality was determined with regard to uniqueness. In addition, a concept for validation in the context of variances was developed. Gaussian error propagation was applied to the entire process simulation in order to estimate the effect of uncertainties from the material parameter identification and the geometry data in deep drawing processes.

Publications

 
 

Additional Information

© 2025 DFG Disclaimer / Copyright / Privacy Policy

Textvergrößerung und Kontrastanpassung