Mechanical properties characterization of the skin and core of a novel composite sandwich structure

Abstract

This study has investigated the mechanical properties of the constituent materials of a novel structural composite sandwich panel developed for structural applications. Properly designed and carefully conducted experiments using coupon specimens following ISO and ASTM test standards were performed to characterize the flexural, tensile, compressive and shear properties of the fiber composite skins and the modified phenolic core of the composite sandwich structure. As a general behavior, the glass fiber composite skins behaved linearly elastic up to failure in both tension and compression with the tensile strength much higher than the compressive strength. The modified phenolic core behaved linearly elastic in tension but exhibited non-linear behavior in compression. The modified phenolic core material exhibited higher strength and modulus in shear and compression compared to the traditional core material systems. The improved mechanical properties of the core structure combined with the high-strength and lightweight glass fiber composite skins suggest a high potential of the novel composite sandwich panel for structural applications. Furthermore, the results of this study provide an understanding of the fundamental behavior of the constituent materials of a novel sandwich structure providing a base knowledge from which further research could continue.