نوع مقاله : پژوهشی
1 تهران، دانشگاه صنعتی امیرکبیر، دانشکده مهندسی نساجی، قطب علمی و پژوهشکده نساجی، صندوق پستی 4413-15875
2 تهران، پژوهشگاه پلیمر و پتروشیمی ایران، پژوهشکده فرایند، گروه کامپوزیت، صندوق پستی 112-14975
عنوان مقاله [English]
The effects of through-the-thickness yarn fineness and distance on the damage behavior of vacuum resin infused 3D carbon-phenolic composites were investigated. For this purpose, the carbon/phenolic composites with different tufting thread fineness (count) and distance ranging from 5.5 mm to 16.5 mm were produced to determine an optimum distance and count in the composites. Three-point bending test results show that the flexural strength of tufting composites may drop 17% to 34 % while through thickness reinforcements set up a mechanical connection between the plies and bridge over delamination cracks to avoid their penetration. The weakness is attributed to damaging effect of tufting method, misallignments of X-Y fibers in presence of Z direction reinforcement and stress concentration effect of produced holes for tufting. On the other hands, Z direction reinforcements prevent fibers delamination. Therefore, the laminate strength was increased and failure mechanism was changed from brittle to ductile fracture. In addition at the same through-thickness yarn count of tufting composites, with the increase in tufting distance, the flexural strength is reduced. But i in the case of samples with tufting distance of 5.5 mm, the flexural strength reduced with increase in thorough-the-thickness yarn count, but for samples with tufting distance of 16 mm, showed some increases with the same count variations. After the failure stress in stress-displacement curve was increased for specimens with Z direction reinforcements.