Interlaminar shear behavior of uhmwpe tensylon® composites in quasi-static mode ii loading

Ultrahigh molecular weight polyethylene (UHMWPE) film composite materials such as Tensylon® HSBD30A are useful for ballistic applications, but quantification of their interlaminar shear behavior is necessary to inform design considerations. This study investigates a double lap shear specimen to determine mode II interlaminar shear properties. Average shear stresses calculated from measured loads and relative displacements calculated from full-field displacement data obtained via digital image correlation are used to produce an approximate traction-separation law. For a representative specimen, interfacial shear strength is calculated to be 3.18 MPa, mode II critical energy release rate is 465 J/m2, and interfacial stiffness is 36.8 MPa/mm. The double lap shear specimen is found to be appropriate for approximating these values, but the potential for complex loading states caused by non-simultaneous crack growth necessitates further investigation into alternative specimen configurations.