Evaluation of compressive and flexural properties of continuous fiber fabrication additive manufacturing technology

This study focuses on the characterization of additive manufacturing technology based on composite filament fabrication (CFF). CFF utilizes a similar method of layer by layer printing as fused filament fabrication but is also capable of reinforcing parts with layers of various continuous fibers into a polymer matrix. Due to the orthotropic characteristics of additive manufacturing based on fused filament fabrication, 3D printed parts may present different mechanical behavior under different orientations of stress. Furthermore, technologies such as CFF allow a range of configurations to fabricate and reinforce the parts. In this study, mechanical characterization of polyamide 6 (PA6) reinforced with carbon fiber was conducted by design of experiment as a statistical method, to investigate the effect of reinforcement pattern, reinforcement distribution, print orientation and percentage of fiber on compressive and flexural mechanical properties. CFF technology 3D print stronger parts than conventional additive manufacturing technologies. Maximized compressive response was achieved with a 0.2444 Carbon Fiber volume ratio, concentric and equidistant reinforcement configuration, resulting in a compressive modulus of 2.102 GPa and a stress at proportional limit of 53.3 MPa. Maximized flexural response was achieved with 0.4893 Carbon Fiber volume ratio, concentric reinforcement and perpendicular to the applied force, resulting in a flexural modulus of 14.17 GPa and a proportional limit of 231.1 MPa.