Fiber-metal laminates (FML) offer enormous potential for lightweight construction due to their outstanding fatigue properties combined with a comparatively low density. In the aerospace industry in particular, their high specific strength can lead to a significant reduction in CO₂ emissions. Furthermore, the linear crack growth in FML allows for simplified monitoring of safety-critical structures, ensuring that components can be relied upon for a long service life. Carbon-fiber-reinforced epoxy resin (CF-EP) is one of the most widely used fiber-reinforced polymers (FRP) and, when combined with steel, can achieve higher strengths than light-metal-based FML. In general, the combination of metals and FRP in FML leads to process-temperature-induced residual stresses (RS) due to differences in thermal expansion coefficients. These can significantly influence the mechanical properties of the component, particularly crack initiation and propagation in the steel. To investigate the controllability and influence of residual stresses, an FML with 1.4310 layers consolidated at various process temperatures is examined. The EP prepreg used can cure at lower temperatures than conventional EP prepreg and enables an early, durable bond between the components. Depending on the process temperatures, the RS in the steel layers are determined using X-Ray diffraction and the resulting fatigue properties are characterized. As a further method for influencing the RS, specimens with a defined pre-strain are subjected to testing with the aim of reducing, neutralizing, and reversing the RS. The two methods for influencing RS are to be compared in terms of their applicability and practicability and cross-validated. The goal is to gain a deeper understanding of the process-structure-property relationship, which is necessary for the customized design of FML.

Duration: 2025 until 2027