Metamortar Composites Reinforced with Re-Entrant Auxetic Cells: Mechanical Performance and Enhanced Energy Absorption

Area of Science:

• Materials Science
• Mechanical Engineering
• Civil Engineering

Background:

• Auxetic materials possess a negative Poisson's ratio, offering superior impact resistance and energy dissipation.
• Integration of auxetic structures into cementitious materials is challenging but promising for advanced composites.
• Metamaterials offer tunable mechanical properties through engineered microstructures.

Purpose of the Study:

• To investigate the mechanical behavior and energy absorption of novel metamortar composites.
• To evaluate the impact of re-entrant auxetic cellular structures embedded in a mortar matrix.
• To explore the potential of 3D printed auxetic cells for enhancing cementitious materials.

Main Methods:

• Fabrication of auxetic cells using various 3D printing filaments (e.g., PLA).
• Creation of hybrid composites by embedding auxetic cells into a cementitious mortar matrix.
• Quasi-static compression testing to determine Young's modulus, yield strength, and energy absorption.

Main Results:

• Auxetic inclusions significantly improved the mechanical performance of the mortar composite.
• PLA-based auxetic cells yielded the highest improvements in Young's modulus, yield strength, and energy absorption.
• Enhanced performance is attributed to synergistic deformation mechanisms and delayed crack propagation.

Conclusions:

• The developed metamortar composite demonstrates superior mechanical properties and energy dissipation capabilities.
• 3D printed auxetic structures are effective in enhancing cementitious materials.
• Findings support the development of metaconcrete for protective, seismic, and infrastructure applications.