Engineers develop innovative material for cars, airplanes capable of self-repairing

Scientists in the United States have developed a new “self-healing” material that could dramatically extend the lifespan of components used in aircraft, cars and other structures—potentially by hundreds of years.

Engineers from North Carolina State University and University of Houston have created a fibre composite capable of repairing a common form of internal damage known as delamination more than 1,000 times. The breakthrough could extend the lifespan of such materials from decades to centuries.

The findings were published in Proceedings of the National Academy of Sciences, as noted in an article by ECONews. 

Fibre-reinforced polymer (FRP) composites—valued for their strength-to-weight ratio—are widely used in planes, cars, wind turbines and even spacecraft. However, they have long been vulnerable to interlaminar delamination, a process in which internal layers begin to separate after cracks form. Once this occurs, structural integrity rapidly declines, often requiring frequent inspections, repairs and part replacements.

“Delamination has been a challenge for FRP composites since the 1930s,” said Jason Patrick, a civil and environmental engineering professor at North Carolina State University and co-author of the study. He added that conventional FRP composites typically last between 15 and 40 years.

According to the study, “this self-healing strategy for interlaminar fracture” enabled by the new material “is repeatable on a scale far exceeding typical composite design lifetimes, thus shedding delamination from structural concern.”

The material resembles a standard FRP composite but incorporates two key innovations. The first is a thermoplastic healing agent that is 3D-printed onto the fibre reinforcement, forming a patterned interlayer between the composite’s laminates. Made from poly (ethylene-co-methacrylic acid), or EMAA, this layer makes the material two to four times more resistant to delamination, helping prevent cracks from forming in the first place.

The second innovation involves embedding thin, carbon-based heating layers within the composite. When an electrical current passes through them, the layers heat up and melt the EMAA interlayer, allowing it to flow into cracks and microfractures and effectively re-bond the damaged structure. In effect, the material can “reweld” itself using its own internal components.

Jack Turicek, the study’s lead author, said the composite begins “significantly tougher” than conventional alternatives and remained resistant to cracking over at least 500 cycles. While its toughness gradually declines with repeated healing, it does so “very slowly.” Researchers estimate components could remain functional for around 125 years with quarterly healing—or up to 500 years with annual repairs.

The development could have far-reaching implications for industries that rely heavily on lightweight composites, particularly clean energy and low-emission technologies, where materials are often difficult to repair or recycle and are typically replaced instead.

If widely adopted, the new composite could significantly reduce industrial waste by enabling repeated repairs of critical components in aircraft, vehicles and wind turbines—cutting down on the need for constant manufacturing and disposal.

By Nazrin Sadigova