Advanced Fiber Breakage Parameter Calibration with X-ray Computer Tomography

Short-carbon-fibre-reinforced thermoplastics are widely used in lightweight structural components due to their low cost, design flexibility, and injection moldability. However, the resulting fibre length distribution (FLD) and fibre orientation distribution (FOD) vary locally and critically affect mechanical performance. Predicting these features requires advanced modelling of fibre orientation and breakage. In this work, we present a calibration method to efficiently define the parameters of the Phelps-Tucker fiber breakage model to further improve the stiffness predictions of injection moulded parts. The study was performed on a PPCF material while X-ray computer tomography (XCT) measurements were combined with a pattern recognition approach to accurately fit the model parameters. Injection molding simulations using the iARD orientation model and Phelps-Tucker breakage model are calibrated with XCT data from a simple, flat injection-molded reference plate. Subsequently, this data is used to conduct the parameter fit, allowing to predict the FLD distribution on an unseen and more complex, three-dimension component, namely an injection molded rotor blade. The method is validated and evaluated for its predictive capability. This workflow enables more accurate structural performance prediction for injection-moulded PP-CF components and supports improved design and simulation strategies for fibre-reinforced thermoplastics.