INNOVATIVE STITCHED PREFORMS FOR HIGH-PERFORMANCE FIBRE-REINFORCED COMPOSITES

摘要

The cost-reduced manufacturing of complex textile preforms used for liquid composite moulding of high-performance fibre-reinforced polymer composites is of significant importance for today's aerospace industry. Stitching technologies are considered to be one of the key approaches towards achieving this challenging goal. However, the potential reduction of the in-plane mechanical composites properties induced by stitching may outweigh the cost savings and the anticipated improvement of the out-of-plane performance. In order to obtain superior overall mechanical composite properties, innovative thermoplastic stitching yarns were utilised here to prepare novel stitched preforms for non-crimped carbon fibre-reinforced epoxy composites. As compared to a standard polyester stitching yarn, low melting-temperature polyamide as well as soluble phenoxy yarns are shown to significantly reduce the maximum fibre undulations in the final epoxy composites; effectively allowing a further pre-stabilisation of the dry performs by thermobonding as well as leading to an optimised composite performance. These promising results emphasize the feasibility and benefits of adopting polyamide and phenoxy stitching yarns in high-performance composites.