• Kim, B. C.
• Rhead, Andrew T.
• Liu, Wenli
• Butler, Richard
• Hallett, Stephen

Abstract

A novel form of fiber steering (Continuous Tow<br/>Shearing (CTS)) which eliminates manufacturing<br/>defects found in other steered fiber techniques, e.g.<br/>tow-overlaps, tow gaps and tow wrinkling, has<br/>recently been developed. By using CTS to steer<br/>fibers in-plane, structures with improved buckling<br/>capacity can be achieved leading to lower mass<br/>designs. Such optimal designs for minimum mass<br/>CTS laminates have been produced using the infinite<br/>strip program VICONOPT. The resulting<br/>distribution of fiber orientation and mass across the<br/>width of these optimized laminates results in regions<br/>of high stress near supports. These regions, which<br/>are vital to the integrity of the CTS laminate, are at<br/>risk of reduction in compressive strength caused by<br/>Barely Visible Impact Damage (BVID). Hence,<br/>using experimental tests combined with a unique<br/>analytical approach, the paper explores the effect of<br/>near support impact damage on the compressive<br/>strength of CTS panels. Results indicate a failure<br/>strain that matches industrial straight fiber<br/>alternatives but that is below the design failure<br/>strain. Hence there is scope for further optimization<br/>of CTS laminates for improved damage tolerance.

Topics

• impedance spectroscopy
• strength
• defect