Interlaminar shear characterization of ultra-high molecular weight polyethylene (UHMWPE) composite laminates

Ultra-high molecular weight polyethylene (UHMWPE) fiber-reinforced composites have received widespread attention in the literature due to their attractive ballistic protection attributes. Recently, investigators are recognizing and demonstrating the significant role that interlaminar shear has on their ballistic performance. In this paper, we present a characterization methodology to quantify the quasi-static interlaminar shear strength and nonlinear interlaminar shear stress-strain response of UHMWPE composite laminates. The methodology uses a tension loaded double-lap coupon design to introduce interlaminar shear loading. Coupon displacement measurements using Digital Image Correlation (DIC) coupled with Finite Element Analysis (FEA) incorporating nonlinear material behavior and traction-separation behavior is an integral part of the data reduction scheme. This research provides a unique methodology for developing interlaminar shear constitutive models for UHMWPE composite laminates, which are critically needed to improve the accuracy of ballistic impact simulations for the development of more efficient armor designs.