Project Details
Projekt
Laminated composites of TRIP/TWIP steels with tailored properties
Subject Area
Mechanical Properties of Metallic Materials and their Microstructural Origins
Term
since 2020
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 448954974
High-alloy TRIP and TWIP steels have been the focus of interest for some years now, especially among car manufacturers, due to their excellent mechanical properties. In the first funding period of the project, fundamental investigations were carried out into the feasibility of TRIP-TWIP, TWIP-TWIP and TRIP-TRIP cladding. It was shown that the material preparation consisting of chemical cleaning followed by surface cleaning by brushing has a decisive influence on the adhesive strength of the material composite. In the case of brushing, it was shown that the geometry of the bristles used significantly leads to the shape and formation of so-called deformation lenses (DL). These can be described as local accumulations of nanocrystalline structure near the brushed surface. These sink further into the surface when a sharp-edged bristle is used. When a rounded bristle is used, as occurs after use, they protrude further from the surface. The influence and contribution of the deformation lenses to the adhesive strength of the overall composite will be further investigated in the following project. Furthermore, the manufacturing process, the cumulative roll cladding (ARB) and its understanding on the model side, will be further developed by introducing shear stresses through the use of different roll radii, which should favour the adhesive strength. Both static and cyclic tests are performed uniaxially to characterise the laminated material composites. These are complemented by microstructural investigations of the bonding zones and characterisation of the Beibly layer. The manufacturing mechanism is accompanied and designed by an already existing simulation program (LayClad). This is to be expanded on the model side using findings from the 1st funding period. In order to assess the utilisation potential of the material composites, their deep-drawing properties in particular are to be compared on the basis of composites between TRIP and TWIP steels and the deep-drawing steel DC06.
DFG Programme
Research Grants
Co-Investigators
Professor Dr.-Ing. Horst Biermann; Professor Dr.-Ing. Ulrich Prahl
