New examples of three-dimensional dilational materials

TL;DR

This paper reviews 2D dilational materials, clarifies misconceptions, and introduces four novel 3D dilational material examples, advancing understanding of their design and properties.

Contribution

It provides new three-dimensional dilational material examples and clarifies the distinction between true dilational materials and similar models.

Findings

Four new 3D dilational materials are introduced.

Clarification of models that appear dilational but are not.

Connections between existing 2D dilational models are established.

Abstract

Two-dimensional dilational materials, for which the only easy mode of deformation is a dilation are reviewed and connections are drawn between models previously proposed in the literature. Some models which appear to be dilational materials, but which in fact are not, are also discussed. Finally, four new examples of three-dimensional dilational materials are given.