Hygrothermal bending analysis of sandwich nanoplates with FG porous core and piezomagnetic faces via nonlocal strain gradient theory

Abstract The bending of sandwich nanoplates made of functionally graded (FG) porous core and electromagnetic layers is explored for the first time through a nonlocal strain gradient theory and a four-unknown shear deformation theory. The proposed model can account for both nonlocal and strain gradient impacts. Therefore, the stiffness enhancement and stiffness reduction processes of sandwich nanoplates are observed. The porosities in the nanoplate are modeled with even and uneven distribution patterns. Six equations of equilibrium are constructed by using virtual work principle. The effects of the porosity factor, externally applied electric and magnetic fields, nonlocal parameter, strain gradient parameter, temperature and moisture parameters, aspect ratio, and side-to-thickness ratio on the static behaviors of FG sandwich nanoplates for simply supported boundary conditions are demonstrated using a parametric study. This article offers comparison treatments for the bending investigation of smart sandwich nanoplates, which can be used in a variety of computational methods. According to the results, deflections induced by negative electric and magnetic potentials behave differently than those brought on by positive electric and magnetic potentials. Other important findings are reached that should aid in the development and implementation of electromagnetic sandwich nanoplate structures.