Hierarchical Fibers with a Negative Poisson’s Ratio for Tougher Composites

Abstract

In this paper, a new kind of hierarchical tube with a negative Poisson’s ratio (NPR) is proposed. The first level tube is constructed by rolling up an auxetic hexagonal honeycomb. Then, the second level tube is produced by substituting the arm of the auxetic sheet with the first level tube and rolling it up. The Nth (N≥1) level tube can be built recursively. Based on the Euler beam theory, the equivalent elastic parameters of the NPR hierarchical tubes under small deformations are derived. Under longitudinal axial tension, instead of shrinking, all levels of the NPR hierarchical tubes expand in the transverse direction. Using these kinds of auxetic tubes as reinforced fibers in composite materials would result in a higher resistance to fiber pullout. Thus, this paper provides a new strategy for the design of fiber reinforced hierarchical bio-inspired composites with a superior pull-out mechanism, strength and toughness. An application with super carbon nanotubes concludes the paper.

Design of Hierarchical Structures for Synchronized Deformations

“…Furthermore, metamaterials that are hierarchically constructed have been reported to exhibit exceptional mechanical properties such as high strength, enhanced toughness and reversible extensibility6922232425262728. Among the metamaterials, auxetic materials, which exhibit negative Poisson’s ratio (NPR), have been studied extensively61011282930. To design auxetic metamaterials with tuneable mechanical properties, the mechanism of “rotating rigid units” is one of the most frequently used principles8910111228.…”

Negative poisson’s ratio in single-layer black phosphorus

“…In contrast, the list of materials that exhibit a negative Poisson's ratio is small, and thus researchers have shown significant interest in finding new materials that exhibit this distinctive property. Negative Poisson's ratio materials are also of great interest because they typically have enhanced toughness and shear resistance, along with enhanced sound and vibration absorption, which has been exploited in fields as varied as medicine 1 , fasteners 2 , tougher composites 3 , tissue engineering 4 , national security and defense, that is, for bulletproof vests and armor enhancement 5 , and many other potential applications [6][7][8] .…”

Fractal Dimension and Parameters of the Grunasena Polymer Systems with Negative Poissonratio

“…У роботах [8][9][10][11] моделюються макромолекулярні системи в яких, при дії зовнішнього силового поля, надмолекулярні утворення та структурні елементи макромолекул дають деформаційний відгук,що зумовлює від'ємний коефіцієнт Пуассона. Отримання та використання полімерних аускетиків на основі нано-, мікро-,мезо-і макроскопічних підходів аналізується в роботах [12][13][14][15][16].…”