Effect of the hexachiral auxetic metamaterial on the 3D wave dispersion characteristics of sandwich nanoplate with foam FGM face layers

Source abstract

Abstract The purpose of this research was to analyze and explore the three‐dimensional wave propagation features of sandwich nanoplates that contained a hexachiral auxetic core layer with graphene‐reinforced FGM symmetric hybrid surface layers. The equations of motion of sandwich nanoplates were obtained using higher order plate theory and nonlocal strain gradient elasticity theory. The auxetic core part of the sandwich nanoplate consists of a hexachiral auxetic structured metal material with Poisson ratio v = 1 and the surfaces are functionally graded as metal and ceramic and are solid and two different foam structures. The 3D wave propagation properties of the sandwich nanoplate were analyzed in detail by considering the auxetic core properties, FGM structure in the surface layer and foam structure properties and the results were presented. It was observed that the hexachiral auxetic structure with metamaterial properties can significantly change the flexural, longitudinal and shear wave propagation characteristics of the sandwich nanoplate. In addition, it has been understood from the analyses that surface layers with different foam structures and material distribution properties have significant effects on the wave propagation characteristics of the sandwich plate. In addition, the results obtained show that sandwich structures can be formed according to the desired wave properties. These findings are at a level that can be used for new applications in the closest application areas, especially in sonar radars, aviation and marine vehicle stealth technologies, and it is expected that the results of the study will make significant contributions to the literature.