Additively Manufactured Hierarchical Auxetic Mechanical Metamaterials

Area of Science:

• Materials Science
• Mechanical Engineering
• Nanotechnology

Background:

• Additive manufacturing allows creation of complex micro- and nanoscale structures, leading to metamaterials with novel properties.
• Auxetic materials, characterized by a negative Poisson's ratio, represent a unique class of metamaterials.
• Hierarchical auxetic materials offer enhanced tunability of mechanical properties.

Purpose of the Study:

• To review research on auxetic materials, with a focus on hierarchical structures.
• To explore the analytical, experimental, and numerical methods used to study auxetics.
• To highlight the advantages and applications of hierarchical auxetic materials.

Main Methods:

• Review of analytical studies on auxetic materials.
• Compilation of experimental data on auxetic material properties.
• Analysis of numerical simulations for auxetic structures.

Main Results:

• Auxetic materials exhibit a negative Poisson's ratio, a property not found in nature.
• Hierarchical auxetic structures provide greater control over mechanical characteristics like stiffness and energy absorption.
• Significant interest exists in hierarchical auxetics due to their versatile property adjustment capabilities.

Conclusions:

• Hierarchical auxetic materials offer advanced control over mechanical properties.
• These materials show promise for biomedical applications requiring high precision, such as stents and implants.
• Further research into auxetic metamaterials can unlock new technological possibilities.