Anelasticity in thin-shell nanolattices

Abstract

In this work, we investigate the anelastic deformation behavior of periodic three-dimensional (3D) nanolattices with extremely thin shell thicknesses using nanoindentation. The results show that the nanolattice continues to deform with time under a constant load. In the case of 30-nm-thick aluminum oxide nanolattices, the anelastic deformation accounts for up to 18.1% of the elastic deformation for a constant load of 500 μN. The nanolattices also exhibit up to 15.7% recovery after unloading. Finite element analysis (FEA) coupled with diffusion of point defects is conducted, which is in qualitative agreement with the experimental results. The anelastic behavior can be attributed to the diffusion of point defects in the presence of a stress gradient and is reversible when the deformation is removed. The FEA model quantifies the evolution of the stress gradient and defect concentration and demonstrates the important role of a wavy tube profile in the diffusion of point defects. The reported anelastic deformation behavior can shed light on time-dependent response of nanolattice materials with implication for energy dissipation applications.

Mechanically-Guided 3D Assembly for Architected Flexible Electronics

“…Apart from the above, many other 3D configurations are also exploited for architected flexible electronics, such as compliant configurations, 191,203,240 complex origami/kirigami configurations, 17,120,122 and architectures with rationally designed microlattices 138,321 that are capable of replicating curved biological surfaces. Figure 17a shows an electronic interface in a curvilinear form, manufactured by the use of curving-induced assembly (associated with local buckling), which was able to conform to many curved surfaces, such as a golf ball.…”

“…Apart from the above, many other 3D configurations are also exploited for architected flexible electronics, such as compliant configurations, ,, complex origami/kirigami configurations, ,, and architectures with rationally designed microlattices , that are capable of replicating curved biological surfaces.…”