Consolidation and Mechanical Properties of Continuous Carbon Fiber Reinforced PA6 Rod Prepared Using a Novel Thermoplastic Pultrusion Technology With Prepreg Tapes

ABSTRACT Fiber‐reinforced thermoplastic composites, distinguished by reprocessability, high toughness, and exceptional durability, are well‐suited to meet the demands of marine engineering applications. This paper presented a novel thermoplastic pultrusion technology utilizing prepreg tapes. The study analyzed the impact of cooling temperature on surface finish quality and consolidation. The temperature distribution, surface roughness, microstructural morphology, and mechanical properties of carbon fiber‐reinforced polyamide 6 (CFRPA6) rods were evaluated. Using the dynamic mesh technique, the transient temperature field within the CFRPA6 rods during pultrusion was simulated, capturing the actual thermal profile. Optimal surface finish, with a roughness of 0.46 μm, was achieved at a cooling temperature of 190°C, attributed to the significant shear force generated between the PA6 resin and the cooling die cavity wall. Under these conditions, the lowest void content of 0.7% was achieved, as the suitable deformation characteristics of the PA6 resin in the transition phase enabled complete bonding of adjacent prepreg tapes under the applied forming pressure. Concurrently, the mechanical properties of the rods attained their peak values: a tensile strength of 2482.2 MPa and a tensile modulus of 129.1 GPa. The primary factor contributing to the reduction in mechanical properties was the voids resulting from inadequate consolidation between adjacent prepreg tapes.