In a groundbreaking development poised to revolutionize the aerospace and energy sectors, researchers have unveiled a novel active flexible metal metamaterial inspired by the unique structure of plant seedcoats. This innovation, led by Wenxin Chen from the Jiangsu Provincial Research Center for Laser Additive Manufacturing of High-Performance Components at Nanjing University of Aeronautics and Astronautics (NUAA), promises to enhance the capabilities of smart morphing aircraft and other advanced applications.
The study, published in the *International Journal of Extreme Manufacturing* (translated as “International Journal of Extreme Manufacturing”), introduces a biomimetic metamaterial designed to mimic the embedded characteristics and wavy interfaces of epidermal cells found in the Portulaca oleracea seedcoat. This design leverages a network honeycomb configuration, manufactured using laser powder bed fusion (LPBF), a cutting-edge additive manufacturing technique.
“Our goal was to create a material that combines the lightweight properties of traditional metamaterials with the strength and active capabilities of shape memory alloys,” explained Chen. The resulting metamaterial exhibits remarkable mechanical properties, including a tunable Poisson’s ratio ranging from −0.21 to +0.47, achieved by regulating the number of cell walls per junction. This tunability allows for precise control over the material’s deformation behavior, making it ideal for applications requiring adaptability and resilience.
One of the most striking features of this metamaterial is its exceptional deformation recovery capability. The hexagonal network honeycombs (HNHs) demonstrated a fracture strain of up to 38% and an impressive shape recovery ratio of 96.10% under thermal activation with 10% pre-programmed strain. This reconfigurable deformation capability enables smooth and continuous deformation within a wide temperature range, from −25° to 25°, making it particularly suitable for morphing wings in aircraft.
The implications for the energy sector are profound. Smart morphing wings equipped with this metamaterial could significantly enhance the efficiency and performance of wind turbines, leading to more sustainable and cost-effective energy solutions. The ability to adapt to varying environmental conditions could also improve the reliability and longevity of renewable energy infrastructure.
“This research represents a significant step forward in the development of active, reconfigurable materials,” Chen noted. “By integrating shape memory alloys into metamaterials, we are opening up new possibilities for engineering applications that require dynamic and adaptive structures.”
As the world continues to seek innovative solutions to address energy challenges, this breakthrough offers a promising path forward. The integration of biomimetic design principles with advanced manufacturing techniques highlights the potential for nature-inspired innovations to drive technological progress. With further development, these active flexible metal metamaterials could become a cornerstone of next-generation energy systems, paving the way for a more sustainable future.