# Deformation Behaviour of Optimised Three-Dimensional Axisymmetric Chiral Auxetic Structures

## TL;DR

This paper introduces optimized 3D chiral structures with unique mechanical properties that could improve biomedical scaffolds and stents.

## Contribution

A novel fabrication method for auxetic axisymmetric chiral structures with enhanced mechanical performance is introduced.

## Key findings

- Optimized ACS structures show superior mechanical properties compared to non-optimized ones.
- Both structures exhibit auxetic behavior with a Poisson’s ratio of about −0.1 up to 40% strain.
- The auxetic capability is promising for biomedical applications like stents and tissue scaffolds.

## Abstract

Background/Objectives: Developing functional tissue constructs via 3D bioprinting relies heavily on scaffold architecture, demanding precise mechanical tunability and high-resolution feature fidelity. Methods: This paper presents a novel approach utilising photocurable resins and resin 3D printing to fabricate auxetic axisymmetric chiral structures (ACSs), which can be used for advanced scaffold engineering. Results: The experimental tests showed that the optimised ACS (optACS) possess superior mechanical properties compared to their non-optimised counterpart. Both analysed structures possess an auxetic behaviour up to 40% longitudinal strain, with a Poisson’s ratio of about −0.1. Conclusions: This auxetic capability is promising for biomedical applications, particularly in developing enhanced stents or tissue scaffolds.