Maneuverable postbuckling of extensible mechanical metamaterials using functionally graded materials and carbon nanotubes

Abstract

Architected, structural materials have been reported with promising enhancement of mechanical performance using the structural method (e.g., mechanical metamaterials MM) and the material method (e.g., composite materials). Here, we develop the extensible, plate-like mechanical metamaterials at the microscale using the functionally graded materials (FGM-MM) and the carbon nanotubes (CNT-MM) to obtain the advanced structural materials with good maneuverability over the postbuckling response. Theoretical models are developed to investigate the postbuckling response of the FGM-MM and CNT-MM subjected to the bilateral constraints, and numerical simulations are carried out to validate the theoretical results. The theoretical models are used to investigate the maneuverability of the postbuckling behaviors with respect to the material properties (i.e., the FGMs and CNTs) and geometric properties (i.e., the corrugated microstructures). The findings show that the corrugation in the MM and composition in the FGMs and CNTs assist in tuning the buckling mode transitions. The reported CNT-MM and FGM-MM provide a novel direction for programming the mechanical response of the artificial materials.