Engineers are looking to create lighter and stronger airplanes using advanced composites made from high-performance fibers embedded in polymer sheets. These composites are extremely lightweight and durable, but the vulnerability lies in the space between layers, where cracks can spread and weaken the material over time, leading to potential catastrophic failure. To address this issue, MIT engineers have developed a technique called “nanostitching,” where microscopic forests of carbon nanotubes are deposited between composite layers, preventing cracks from spreading between layers like ultrastrong Velcro. In experiments with thin-ply carbon fiber laminate, nanostitching improved crack resistance by up to 60%, addressing the main vulnerability of advanced composites.
The concept of nanostitching involves growing vertically aligned carbon nanotube forests that act as reinforcements between composite layers. The dense fibers grip and hold the layers together, significantly improving the material’s resistance to cracks. This fiber-reinforced compound enhances the strength and durability of composites, providing a solution to the main weakness of these materials. The researchers have shown that nanostitching can make composites strong and tough, preventing cracks from growing and ensuring the longevity and safety of next-generation aircraft.
The nanostitching technique was tested on thin-ply carbon fiber laminates, a new composite technology that is thinner and potentially more resilient than standard composites. By combining nanostitching with thin-ply technology, the researchers aimed to create more resilient aircraft, aerospace structures, and vehicles. The experiments conducted by the team showed that nanostitching improved the composite’s resistance to delamination, a common issue that can lead to hidden damage and eventual failure. The results demonstrated that nanostitching significantly increased the toughness and resistance of the composite, making it a promising solution for enhancing the performance of advanced materials.
The experiments led by Carolina Furtado, a former MIT visiting graduate student, postdoc, now a professor at the University of Porto in Portugal, showcased the effectiveness of nanostitching in preventing delamination and improving crack resistance. By growing carbon nanotube forests and embedding them between composite layers, the researchers were able to create a stronger and more durable material that withstood various delamination modes. The nanostitched samples showed up to 62% greater toughness and resistance to cracks compared to conventional composites, highlighting the potential of this technique for enhancing the performance of composite materials.
The researchers see nanostitching as a game-changer in composite technology, with the potential to make any vehicle or structure incorporating conventional composites lighter, tougher, and more resilient. This innovative approach allows for selective reinforcement of problematic areas, such as bolted joints or regions prone to delamination, providing a significant opportunity to improve the overall performance and safety of composites. By implementing nanostitching in various applications, engineers can enhance the structural integrity and longevity of composite materials, leading to safer and more reliable aircraft, vehicles, and infrastructure.
Overall, the development of nanostitching represents a significant advancement in composite technology, offering a practical solution to improve the strength and durability of advanced materials. By utilizing carbon nanotubes to reinforce composite layers, engineers can prevent cracks and delamination, increasing the resilience and longevity of structures and vehicles. The results of the study demonstrate the potential of nanostitching to revolutionize the aerospace industry and other sectors that rely on composites, paving the way for safer, more efficient, and more sustainable transportation and infrastructure solutions.
