Tensile Testing Jig Unit for Foams and Foam-Cored Fiber-Reinforced Plastic Sandwich Composites

Polymer foam is applied as a structural core material in polymer foam-cored fiber-reinforced plastic sandwich composites. Recently, the application of polymer-based foam as a lightweight core component for structural materials has been increasing. It is therefore imperative to develop a system to objectively evaluate the performance of foam and foam-cored composite materials; however, polymer-based foam is vulnerable to compressive forces. When a sample is fixed by a compressive force, the force is transmitted to the foam, which causes deformation and stress concentration, making it is difficult to accurately measure the tensile properties of the sample. To confirm the performance of this method, a tensile test was simulated by the finite element method, and the strain-stress curves obtained using a tensile tester and digital image correlation were compared with those obtained using the existing method. The specimen-fixing jig designed herein could more accurately evaluate the tensile properties of specimens that are vulnerable to compressive forces than the existing method.