Tunable bending in graphene‑origami hybrid shell structures for adaptive aerospace applications

Abstract

This work investigates the tunable bending deflection in doubly-curved shells featuring a functionally graded auxetic metamaterial core with graphene origami (FG-GOEAM), coupled with piezoelectric and piezomagnetic surface layers. The multilayer core is engineered with variable graphene origami (GOri) content to achieve controlled negative Poisson's ratio effects and tailored mechanical response. A sinusoidal higher-order shear deformation framework is adopted to capture the kinematic behavior of the hybrid shell system. Governing relations are established via Hamilton’s variational principle and solved analytically under simply supported edge conditions using a Navier-type expansion. A parametric investigation is conducted to assess the sensitivity of bending deflection and normal stress to GOri weight fraction, folding degree, spatial distribution pattern, thermal environment, and thickness of the smart face sheets. Results reveal that the bending response is governed by a coupled interaction between the FG-GOEAM core characteristics and the piezoelectric/piezomagnetic layers, demonstrating that tunability is achieved through combined rather than independent material adjustments.