Thermo-mechanical simulation and forming mechanism investigation for hot stamping of CFRTP hat beams

Hot stamping of continuous fiber-reinforced thermoplastic composites (CFRTPs) offers a fast and cost-effective route for manufacturing lightweight components for automotive and aerospace applications. However, unsuitable process conditions can cause defects and reduce part performance. This study examines how key process parameters affect the forming behavior and post-forming damage of CFRTP components. A plain-weave glass fiber/polypropylene (GF/PP) hat-shaped beam was selected as the forming part. The parameters of the MAT_249 constitutive model were calibrated, and a coupled thermo-mechanical simulation model was developed and validated against hot stamping experiments. The mean absolute errors (MAEs) of the predicted thickness and fiber angle were 3.94% and 2.54%, these results demonstrate the accuracy of the simulation model. The effects of ply orientation, blank-holder force, initial blank temperature, blank-holder width, and mold temperature on fiber shear angle, thickness distribution, and damage were then examined. The forming history was used to relate changes in shear angle and thickness to the development of matrix and fiber damage. The results show that ply orientation, blank-holder force, and initial blank temperature have the strongest effects on part quality. Appropriate control of these parameters can therefore improve the forming quality of CFRTP hat-shaped beams.