Estimation of the Molding Thickness of Knitted Fabric Reinforced Thermoplastic Composites Produced by Hot-pressing

Abstract

Based on some assumptions, this study derives an equation that estimates the theoretical molding thickness h_c of knitted fabric reinforced thermoplastic composites (KFRTC). This is required for controlling the actual molding thickness of KFRTC that are produced by hot pressing knitted preforms made from reinforcing fiber/matrix fiber commingled yarns. The relationship between the optimum actual molding thickness h that can result in composites with higher tensile strength and lower void content and the theoretical molding thickness h_c are also determined experimentally in this study. It is found that the composites produced can have higher tensile property and lower void content when h and h_c satisfy h = kh_c (0.85 ≤ k ≤ 0.95). This estimation of h contributes to manufacturing KFRTC.

Keywords

knitted fabric reinforced thermoplastic composite (KFRTC)commingled yarn hot pressing theoretically optical molding thickness actually optical molding thickness.

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