Simulation-based development of formable 2D non-crimp fabrics with integrated structure-influencing yarn systems for 3D fiber-reinforced composites

• Applicants: Professor Dr.-Ing. Chokri Cherif; Dr. Thomas Gereke
• Subject Area: Lightweight Construction, Textile Technology
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 567552967

The central aim of lightweight structural design is to minimize weight while maintaining high load-bearing capacity and durability. Compared to aluminum and steel, fiber-reinforced composites offer weight savings of up to 70% with the same performance. However, this lightweight construction method poses challenges, particularly in the production of complex component geometries based on two-dimensional textiles.A crucial production step is draping of the preform, which is influenced by the shape, the technology and the material. With complex geometries, draping effects such as gaps, wrinkling, fiber misalignment and resin-rich zones often occur, which impair the mechanical properties. A fiber misalignment of only 10° can reduce the stiffness of a composite component by up to 30 %. To compensate for this, additional fabric layers are often used, which reduces the degree of lightweight design and increases material consumption.Multiaxial non-crimp fabrics, consisting of multiple unidirectional layers, offer a promising solution for the industrial production of load-adapted, customized textile structures. However, the drapability of complex components remains a challenge. The shear deformability and bending stiffness of the textiles are decisive factors, making conventional preform manufacturing processes prone to errors and resource-intensive.The production process envisaged in the project is intended to extend the traditional draping process by means of forming and densification processes and corresponding simulation models. The aim is the simulation-based development of novel non-crimp fabric structures that adapt optimally to complex component geometries without creating gaps or distortions. A central aspect is the development of 2D fabrics with integrated thread systems and thread reserves that can be formed three-dimensionally and densified by thermal shrinkage. The aim is to increase the fiber volume content to up to 60%, achieve a uniform fiber distribution and reduce the deviation in fiber orientation to less than 4° to fully exploit the reinforcement fibers' potential. This is to be analysed using further developed eddy current technology.Research focuses on simulation-based methods for analyzing material-structure-property relationships and on the development of technology modules for the production and subsequent forming and densification of continuously windable, formable 2D non-crimp fabrics with integrated structure-influencing thread systems for complex 3D components. Systematic material analyses are carried out in order to better understand the interactions between the thread systems, densification and mechanical properties of the components. Forming simulations are intended to provide a deeper understanding of the structure-property relationships, enabling targeted predictions about the behavior of the novel non-crimp fabric structures and to identify potential limitations in forming and densification.

• DFG Programme: Research Grants