Skin‐Core Hybrid Thermoplastic Composites Fabricated via Integrated Multi‐Material Additive Manufacturing and Compression Molding

ABSTRACT

The ability to tailor material properties within a single composite structure is becoming increasingly important for lightweight applications requiring a balance of stiffness, toughness, and thermal stability. In this study, multiplexed co‐extrusion was integrated with additive manufacturing–compression molding (AMCM) to fabricate skin–core thermoplastic composites. The hybrid consisted of a glass‐fiber‐reinforced polycarbonate (PC/GF) skin surrounding a carbon‐fiber‐reinforced acrylonitrile butadiene styrene (CF/ABS) core, combining the heat and impact resistance of PC/GF with the high stiffness of CF/ABS. Morphological analysis confirmed preservation of the skin–core architecture and preferential carbon‐fiber alignment along the print direction. Rheological characterization revealed shear‐thinning behavior in both materials and a reduction in their viscosity contrast with increasing angular frequency. CF/ABS exhibited the highest tensile strength (84.27 MPa) and modulus (14.92 GPa), whereas the hybrid achieved a tensile strength of 64.16 MPa and a flexural modulus of 5.19 GPa, the latter representing an approximately 56% increase relative to PC/GF. Under the tested flatwise, print‐direction impact configuration, the hybrid exhibited approximately 130% and 15% higher impact resistance than CF/ABS and PC/GF, respectively, demonstrating the influence of the skin–core architecture on impact response. The hybrid also exhibited a heat deflection temperature approximately 9°C higher than that of CF/ABS while retaining distinct thermomechanical transitions associated with both constituent phases. These results demonstrate the potential of the integrated multiplexed co‐extrusion and compression‐molding process for manufacturing architected thermoplastic composites with tailored mechanical and thermomechanical performance for lightweight structural applications.