Abstract: The formation process of composite materials alters the internal structure, which subsequently impacts the properties of the composite component. This is especially evident when the geometry of the part is complex; the forming of the woven composite may result in alterations in the warp and weft angles. To investigate the fiber reorientation induced by forming processes and to identify the influencing factors, a finite element model (FEM) employing a hypoelastic constitutive law was developed. This model was validated through hemispherical forming experiments, focusing on two primary aspects: fiber reorientation distribution and the boundary profile of the prepreg. Moreover, the paper extends the validation to U-shaped structures, where forming experiments and simulations are conducted to further substantiate the model’s predictive capability regarding fiber reorientation. Additionally, the impact of various factors such as the coefficient of friction, blank holding force (BHF), and blank holding area (BHA) on fiber reorientation is extensively analyzed through the forming simulations of the U-shaped structure. The results show that these process parameters are important factors affecting fiber reorientation and should be optimized during thermoforming.

Key words: woven composites, thermoforming, finite element model, fiber reorientation, parametric studies