Path‐following roller compaction for enhanced mechanical strength of short carbon fiber reinforced nylon in 3D printing

Abstract Material extrusion 3D printing often suffers from voids and poor interlayer bonding, which significantly weaken the mechanical properties of the printed parts. To address these issues, this paper proposes a path‐following roller compaction method aimed at reducing voids and improving interlayer bonding in short carbon fiber reinforced nylon parts. A mathematical model is developed to explain how roller compaction enhances interlayer bonding strength and reduces porosity, with quantifiable improvements. A dual‐roller system is designed to dynamically adjust to varying printing paths, ensuring effective layer compaction and compensating for layer height changes induced by roller pressure. Tensile and three‐point bending tests were performed to evaluate the impact of roller compaction depth on mechanical properties. Results show that maximum tensile strength improved by 141.2%, tensile modulus by 82.8%, bending strength by 62.4%, and bending modulus by 97.6%. This innovative method provides a significant enhancement in the performance and reliability of large‐scale, high‐performance rapid 3D printing applications. Highlights Establish a porosity suppression model based on roller compaction. Propose a nonlinear path‐following roller compaction method. The mechanical properties of the structure were significantly improved after roller compaction.