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Dynamics of Polymeric Re-Entrant Auxetic Structures: Cyclic Compression Studies
Julian Plewa1, Małgorzata Płońska1, Grzegorz Junak2
1Faculty of Science and Technology, Institute of Materials Engineering, University of Silesia in Katowice, 75 Pułku Piechoty Str., 41-500 Chorzów, Poland.
Polymers
|April 28, 2025
Summary
This study explores polymeric auxetic structures under cyclic compression, revealing hysteresis loops and the Mullins effect. Auxetic material behavior, including negative Poisson
Area of Science:
- Materials Science
- Mechanical Engineering
- Polymer Science
Background:
- Auxetic materials exhibit unique deformation characteristics.
- Re-entrant structures offer tunable mechanical properties.
- Understanding dynamic behavior under cyclic loading is crucial for material design.
Purpose of the Study:
- To investigate the dynamic behavior of printed polymer re-entrant structures under cyclic compressive loading.
- To analyze the strain-force relationships and identify hysteresis loop characteristics.
- To determine the influence of structural design and loading amplitude on mechanical response and Poisson's ratio.
Main Methods:
- Fabrication of re-entrant unit cell structures from polymers.
- Application of cyclic compressive loading with varying amplitudes within the elastic range.
- Measurement of strain-force relationships to obtain hysteresis loops.
- Calculation of Poisson's ratio based on dimensional changes.
Main Results:
- Strain-force relationships exhibited hysteresis loops, indicating energy dissipation.
- The Mullins effect was observed in the polymeric auxetic structures.
- Hysteresis loop width was dependent on structural closure and compression amplitude.
- Negative Poisson's ratio values (below -1) were determined.
- Increased strut thickness led to a decrease in the magnitude of the negative Poisson's ratio.
Conclusions:
- Polymeric re-entrant structures display complex dynamic behavior under cyclic compression.
- The observed Mullins effect and hysteresis are key characteristics of these auxetic materials.
- Structural parameters and loading conditions significantly influence the mechanical response and auxetic properties.
- The study confirms the tunability of negative Poisson's ratio by adjusting strut thickness.
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