Bending Properties of Sandwich Beams with Fiber Metal Laminate Face Sheet

Abstract

Sandwich structures are widely used in aerospace, high speed trains and marine applications because of lightweight and high in-plane and flexural stiffness. Sandwich structures consist of two thin face sheets and a core. Face sheets usually are made from highly stiff and highly strong materials; In general, the face sheets may be of different metal or composite layers. Both metal and composite face sheets have advantages and disadvantages, and searching for new materials with better properties is in progress. In this paper flexural behavior of a new generation sandwich beams with fiber metal laminate (FML) face sheets were investigated experimentally. Three groups of specimens with different layer arrangements of face sheets consist of (Al/GE (0-90)/GE(90-0)/Al), (Al/GE(0-90)/Al/GE(90-0)) and (GE(0-90-0-90-90-0-90-0)) and 40 kg/m3 polyurethane foam core were made and tested. The results show that sandwich beams with FML face sheets have better resistance against local loads, while composite faces are weak against intense loads. Also, FML faces are lighter than metal face sheets and have better connection to foam core. Also, a simple classical theory was used to predict the force-deflection behaviour of sandwich beams in elastic region. Good agreement between the experimental results and analytical prediction were obtained. Sandwich beams with FML face sheets have larger elastic region than beams with composite face sheets therefore agreement between the analytical and experimental results in these specimens are in larger area.

Keywords

• : sandwich beam
• fiber metal laminate
• 3- point bending
• glass fiber
• layer arrangement