2024 Volume 50 Issue 4 Pages 135-141
Carbon fiber-reinforced plastics (CFRPs) are known for their high specific strength and stiffness; however, interlayer delamination occurs inside CFRPs owing to impact. Previous studies have demonstrated the recovery of the compressive strength in CFRP laminates using polyamide 6 as the matrix through thermal fusion bonding. However, because the actual structure is larger than the hot press, fibers and resin in the carbon fiber-reinforced thermoplastic (CFRTP) laminates may flow out from the heated and compressed areas. To solve this problem, we employed specimens larger than the press section to conduct repairs while cooling the portions exposed outside the press. The laminates were first subjected to indentation tests to introduce delamination, followed by repair under three conditions: 5 min at 306 and 316℃ and 50 min at 316℃. The results indicated successful delamination repair without flow out of the fiber and matrix. In compression tests, the compressive strengths of the repaired specimens were comparable to those of virgin specimens. However, the compressive strength of the intact parts decreased as the repair temperature and time increased. This paper presents a viable repair method for delamination in CFRTP laminates, which can be used for preserving the structural performance of CFRTP components.
