Compressive strength degradation of the curved sections of 3D-printed continuous carbon fiber composite

In this study, we proposed a test method to evaluate the strength of a curved section of 3D printed continuous carbon fiber reinforced thermoplastics. Curved beam tests were conducted using L-shape specimens to evaluate the strength of the curved section. To test thin L-shape specimens, test jigs were designed. In this process, finite element analyses were conducted to testify that the designed jigs were appropriate for evaluating the strength of the curved section. Several L-shape specimens with different geometries, respectively, were tested to evaluate the effect of radius on the circumferential strength. Additionally, the failure mechanism was investigated by observing the inner structure via X-ray CT. These tests revealed that compressive failure first occurred and that the compressive stress decreased as the radius became smaller.