Lightweight structures directly contribute to the sustainability of aviation, as their use reduces the structural weight of aircraft which in turn reduces fuel burned during flight. One family of lightweight structures are metal-coated polymers. Hybrid nanocrystalline microtrusses are a member of this family. These structures are fabricated by 3D printing complex truss-like structures out of polymer material, and electrodepositing nanocrystalline metal onto the polymer. Recent work has shown that buckling instabilities govern the strength of these systems. Hence this study focuses on modelling local shell buckling, one of the critical buckling mechanisms. This paper briefly reviews existing models for filled-shell local shell buckling, and outlines the development of an improved model.

Increasing the environmental sustainability of aviation is a key design goal for commercial aircraft for the foreseeable future. From the perspective of structural engineering, this is accomplished through reducing the mass of aircraft components and structures. Advanced manufacturing techniques offer new avenues for design, enabling more complex structures which can have highly tailored properties. One advanced manufacturing concept is the use of 3D printed polymer preforms that are coated with nanocrystalline metal through electrodeposition. This enables the use of high-performance materials in virtually any geometry. To exploit this manufacturing approach, it is incumbent to have well-established mechanical models of the behavior of such hybrid structures. In particular, hybrid polymer-nanometal structures tend to fail due to compressive instabilities. This paper describes a model of local shell buckling, a typical compressive instability, as it applies to hybrid polymer-nanometal structures. The analysis depends upon the Southwell stress function model for radially loaded solids of rotation, and couples this with the Timoshenko analysis of local shell buckling. This combination is applicable to a range of practical configurations for truss-like hybrid structures.