Fabrication and Evaluation of Multilayered Polyurethane Foam Core Sandwich Panels for Static Flexural Stiffness

Light weight sandwich laminated panels are increasingly being used as structural materials for a wide variety of applications in marine, aerospace, automobile, transportation and electronic packing sectors. These sandwich panels are separated by stiff and strong face sheets, with low density core such as polyurethane foam, corrugated polyvinyl chloride sheets, aluminum honeycomb or polystyrene cellular solids. The core provides the necessary section modulus as well as shear rigidity at a low weight premium and the facing provide the adequate flexural rigidity and strength. Such a combination is being referred to as sandwich effect. The application of sandwich panels is of recent origin and their heterogeneous nature makes the understanding of static behavior extremely complex. In this study attempts have been made to study the effect of change thickness of Fiber reinforced Polymer (FRP) facing sheets and inserts. The total thickness of the sandwich panels is kept constant to 20 mm. three point and four point tests are conducted in digital flexural testing machine according to ASTM standards. The span length during testing have been varied that is 200 mm and 400 mm. the results have been analyzed to conclude which combination of panel containing varied thickness of face sheets and inserts give best stiffness values. (C) 2014 The Authors. Published by Elsevier Ltd.