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Studies of Auxetic Structures Assembled from Rotating Rectangles
Julian Plewa1, Małgorzata Płońska1, Grzegorz Junak2
1Faculty of Science and Technology, Institute of Materials Engineering, University of Silesia in Katowice, 75 Pułku Piechoty Str. 1a, 41-500 Chorzów, Poland.
Materials (Basel, Switzerland)
|April 9, 2024
Summary
This study analyzes modified rotating polygon auxetic structures. Introducing pivot points reveals correlations between Poisson
Area of Science:
- Materials Science
- Mechanical Engineering
- Computational Mechanics
Background:
- Auxetic materials exhibit a negative Poisson's ratio, expanding when stretched.
- Rotating polygon structures are known auxetic systems.
- Modifications to existing auxetic structures can unlock new properties.
Purpose of the Study:
- To analyze a modified rotating polygon auxetic structure.
- To investigate the impact of pivot point introduction on auxetic behavior.
- To explore correlations between geometric parameters and Poisson's ratio.
Main Methods:
- Geometric analysis of a modified rotating polygon unit cell.
- Derivation of formulas for linear dimensions and Poisson's ratio.
- Parametric study of the influence of rectangle side ratios and pivot point placement.
Main Results:
- Established previously unexplored correlations between Poisson's ratio, geometric parameters, and structural opening.
- Demonstrated that Poisson's ratio is dependent on the degree of structural opening during stretching.
- Identified critical parameter limits leading to the loss of auxetic properties (positive Poisson's ratio).
Conclusions:
- The modified rotating polygon structure exhibits tunable auxetic properties.
- High negative Poisson's ratio values are achievable with specific geometric configurations (elongated rectangles, small opening angles).
- Understanding these parameter dependencies is crucial for designing advanced auxetic materials.
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