Can confined mechanical metamaterials replace adhesives?

TL;DR

This paper explores the potential of mechanical metamaterials to serve as adhesive interfaces, proposing a new application that could replace traditional adhesives and shift paradigms in material joining.

Contribution

It introduces a methodology for evaluating confined lattice metamaterials as adhesive replacements within fracture mechanics, combining theoretical and numerical analyses.

Findings

Identifies critical parameters for designing confined lattice metamaterials.

Develops failure maps indicating susceptibility to failure modes.

Explores both stretching and bending dominated lattices.

Abstract

The subject of mechanical metamaterials has been gaining significant attention, however, their widespread application is still halted. Such materials are usually considered as stand-alone, vis-\`a-vis all characteristic length scales being associated solely with geometry of material itself. In this work we propose novel application of mechanical metamaterials as interface regions joining two materials with potential of replacing bulk adhesives. This idea leads into paradigm shifts for both metamaterials and adhesive joints. In specific, we outline methodology for testing and evaluating confined lattice materials within fracture mechanics framework. The theoretical and numerical approaches are inter-winded, revealing a set of critical parameters that needs to be considered during design process. Lattices that are stretching and bending dominated are explored and failure maps are proposed, indicating susceptibility to a certain failure mode depending on level of confinement and characteristic dimension of each lattice's unit cells.