Bioinspired engineering study of Plantae vascules for self-healing composite structures

Area of Science:

• Materials Science
• Composite Materials
• Bio-inspired Engineering

Background:

• Composite materials are crucial in many industries but lack inherent self-healing capabilities.
• Current self-healing methods often incur a significant mass penalty.
• Vascular networks offer a potential solution for integrated self-healing functionalities.

Purpose of the Study:

• To investigate the creation of a plant-inspired vascular network in fibre-reinforced polymer composite laminates.
• To assess the self-healing potential and mass penalty of such a vascular system.
• To characterize the influence of vascule orientation on mechanical behaviour and damage morphology.

Main Methods:

• Utilized a 'lost-wax' technique to introduce orthogonal hollow vascules within a carbon fibre-reinforced epoxy polymer composite laminate.
• Experimentally characterized mechanical behaviour using compression-after-impact tests.
• Employed ultrasonic C-scanning and micro-CT X-ray to analyze internal vasculature and impact damage interactions.

Main Results:

• Vascular network introduction was successful, inspired by plant ray cell structures.
• Damage morphology was influenced by vascule orientation following a 10 J low-velocity impact.
• Residual compressive strength decreased to 70% (parallel) and 63% (transverse) of undamaged strength, indicating an impact-induced breach of the vasculature.

Conclusions:

• The bio-inspired vascular concept offers a promising approach for self-healing in composite materials with minimal mass penalty.
• Vascular orientation significantly influences damage morphology and residual mechanical properties after impact.
• The study demonstrates the feasibility of integrating self-healing functionality without compromising structural integrity prior to damage.