Measuring polymer composite interfacial strength
Polymer matrix composites are seeing increased use in the automotive industry due to their significant potential for vehicle mass reduction, but are hampered by the lack of sufficient material models to predict their plastic deformation. Material models using fiber–matrix interfacial strength as an input show promise in predicting the inelastic mechanical properties. This study presents a new method to directly measure the interfacial shear and normal strengths via a model system. The lap-shear test is modified to measure the interfacial shear strength, while a modified tensile test is conducted to measure the interfacial normal strength. The degree of cure and the addition of silane coupling agents are introduced as independent variables to examine their effect on interfacial strengths. The experimental results for a glass/epoxy system are reported and are validated against traditional interfacial measurement tests. The lap shear test is a rapid, cost-effective tool to quantitatively measure the interfacial strength of a polymer composite system.
http://dx.doi.org/10.1016/j.compositesb.2013.10.069
