Title: An Experimental Study of the Creep Behavior of Braided Composites

Authors: Ahmed S. Ead, Cagri Ayranci, Jason P. Carey

DOI: 10.33599/nasampe/s.19.1408

Abstract: There are many composite manufacturing techniques, but recently braiding composites have been gaining popularity. Braided composites have been extensively studied – experimentally, analytically and numerically – in literature in terms of their tensile, compressive and torsional properties. No studies, however, have attempted to understand the creep behavior of these braided composites. Consequently, this work sought to investigate creep behavior of braided composites. Kevlar® braided samples were manufactured at three braid angles (35, 45 and 55 degrees) and loaded at three different percentages of the failure load (40 %, 50 % and 60 %) with loads sustained for two days. Strain was measured using a virtual extensometer. Strain versus time curves were plotted for the different samples and used to calculate the predicted time to failure. Results from this work show that Kevlar® braided composites do exhibit creep behavior which has not been shown before in literature. Furthermore, initial results indicate that braided composites at lower braid angles and lower percentages of the failure load have longer predicted functional life. Careful consideration needs to be made to braid geometry and loading conditions when using braided composites in applications where creep is relevant.

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Conference: SAMPE 2019 - Charlotte, NC

Publication Date: 2019/05/20

SKU: TP19--1408

Pages: 15

Price: FREE