Influence of porosity on the fundamental natural frequencies of FG sandwich beams

Abstract

The concept of functionally graded materials (FGMs) is being actively investigated in sandwich beam design to enhance the durability of the sandwich structure. However, during the manufacturing of FGMs, some technical issues might cause porosities in FGMs, resulting in noticeable changes in mechanical characteristics of sandwich construction. Using an enhanced shear deformable beam theory, the influence of porosity on the fundamental natural frequencies of functionally graded (FG) sandwich beams having simply supported ends is examined in this study. To do so, the material properties of the FG sandwich beam (FGSB) are supposed to change incessantly in conjunction with the thickness, depending on the volume fraction of constituents specified by the modified rule of the mixture, which contains the volume fraction of porosity. The FGSB has two FG face sheets and a homogeneous hardcore (ceramic), and the FGSB has two FGface sheets and a homogeneous softcore (metal) are examined. The outcomes are reported for two constituent metal-ceramic FGSBs with a power-law change of the volume fractions of the constituents across the thickness. Consequently, it is seen that the volume fraction of porosity, power-law index, length to thickness ratio, and the thickness of the FG layer have a substantial impact on the dynamic response of FGSB according to the findings.