The effect of UV irradiation on polyamide 6/carbon-fiber composites based on three-dimensional printing

In this research, we demonstrate the effect of ultraviolet-C (UV-C) irradiation of Polyamide 6/carbon-fiber (PA6/CF) composites. The PA6 and PA6/CF composites were fabricated using a fused deposition modeling type 3D printer with a single spool. These specimens were exposed for 0, 1, 3, 5, and 7 days under UV-C light irradiation. After exposure, the specimens were observed and characterized with contact angle measurements, Fourier transform infrared analysis, 3D fluorescence spectroscopy analysis, tensile tests, and scanning electron microscopy. As a result, PA6 was found to be more photo-oxidative degraded than PA6/CF. Furthermore, the 3D fluorescence images and emission spectra were shown to successfully coincide with the results of the photo-oxidative degradation reactions of PA6 and PA6/CF. In addition, the tensile test results showed a dramatic decrease in PA6 while PA6/CF did not decrease much, indicating that CF is useful not only as a reinforcement of the composite but also for UV protection.