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Tensile Testing of Aged Flexible Unidirectional Composite Laminates for Body Armor



Amy E. Engelbrecht-Wiggans, Faraz A. Burni, Amanda L. Forster


Flexible Unidirectional (UD) composite laminates are commonly being used for ballistic- resistant body armor. These laminates are comprised of UD layers, each constructed by laminating thin layers of high-performance fibers held in place using binder resins and thin polymer films, with the fibers in each layer oriented parallel to each other. As these materials are used in body armor, it is important to investigate their long-term reliability, particularly with regards to exposure to temperature and humidity as these are known causes of degradation in other materials considered for body armor. This work investigates the tensile behavior of a PPTA flexible UD laminate aged for up to 150 days at accelerated conditions of 70 °C and 76 % relative humidity. Tests were performed at three different crosshead displacement rates and three different lengths were also considered. The effect of ageing on the mechanical properties of the material was minimal overall, but more significant reduction was observed on the longer specimens tested at slower rates.
Journal of Materials Science


Composite laminate, flexible composite, strip tensile testing, body armor, aramid, hydrothermal ageing


Engelbrecht-Wiggans, A. , Burni, F. and Forster, A. (2019), Tensile Testing of Aged Flexible Unidirectional Composite Laminates for Body Armor, Journal of Materials Science, [online], (Accessed May 28, 2024)


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Created September 27, 2019, Updated May 20, 2020