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Auxetic Behaviour of Rigid Connected Squares
Julian Plewa1, Małgorzata Płońska1, Grzegorz Junak2
1Faculty of Science and Technology, Institute of Materials Engineering, University of Silesia in Katowice, 1a, 75 Pułku Piechoty Str., 41-500 Chorzów, Poland.
Materials (Basel, Switzerland)
|August 12, 2023
Summary
This study analyzes rotating rigid unit (RRU) auxetic structures with negative Poisson
Area of Science:
- Materials Science
- Mechanical Engineering
- Structural Mechanics
Background:
- Auxetic materials exhibit a negative Poisson's ratio, expanding in all directions when stretched.
- Traditional auxetic structures often rely on complex geometries or specific material properties.
- Rotating Rigid Unit (RRU) structures offer a novel approach to auxetic behavior.
Purpose of the Study:
- To analyze the geometric properties of RRU auxetic structures.
- To validate the performance of these structures through physical models.
- To explore their potential industrial applications.
Main Methods:
- Geometric analysis of rotating square units connected at pivot points.
- Construction and testing of physical models assembled from square units.
- Comparison of experimental results with geometric predictions.
Main Results:
- RRU structures demonstrate stable functionality under tension and compression.
- Geometric analysis accurately predicts expansion and porosity.
- Physical models confirm the predicted dimensional changes.
Conclusions:
- Modified rotating squares yield physical structures with auxetic properties.
- The assembly method is suitable for robotic fabrication.
- Potential applications include expansion joints and mechanically tunable porous structures.
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