Flexural Behavior of Biaxial Braided Composites

Abstract

Braided composites have more balanced properties than traditional tape laminates, and have potentially better fatigue and impact resistance due to the interlacing. The natural conformability of biaxial braided tubes makes it the ideal preform for three-dimensional complex components. Braid tube fits on complex components with ease just like pulling socks on feet. Thus cutting, stitching, or manipulation of fiber placement is not needed, as in the use of woven fabrics. Biaxial braided composites find applications in aerospace, automotive, construction, medical, and recreational industry. Some of the products are automobile cross beams, lamp and utility poles, prosthetic limbs, hockey sticks, baseball bats, and bicycle components. Vacuum assisted resin transfer molding (VARTM) is a low-cost manufacturing process with the capability of manufacturing complex parts with higher fiber volume fractions than those from hand lay-up. To utilize the braided composites to the fullest advantage (and hence to avoid underutilization), it is necessary to understand their behavior under flexural, impact, and fatigue loading. Flexural loading is dominant in the above-mentioned applications of braided composites. This research addresses the effect of braid angle on flexural behavior and failure mechanisms of biaxial braided composites manufactured using VARTM.