U.S. engineers have developed a fiber composite capable of repairing internal damage more than 1,000 times, a breakthrough that could extend the service life of aircraft, cars, and wind turbines for centuries, according to ecoticias.com.
In laboratory tests, the material successfully repaired delamination, a common failure in composite structures. Researchers estimate this technology could stretch the typical lifespan of composite parts from a few decades into several centuries.
Modern clean-energy and low-emission technologies rely heavily on lightweight composites that are difficult to repair and recycle. By allowing critical components to be repaired in place, the technology could significantly reduce industrial waste by decreasing the need to manufacture and scrap massive parts.
Solving the delamination problem
Fiber-reinforced polymer (FRP) composites are widely used in spacecraft, cars, and wind turbines because they provide high strength without significant weight. However, they suffer from interlaminar delamination, where internal layers separate after cracks form.
Jason Patrick, a civil and environmental engineering professor at North Carolina State University and corresponding author of the research, noted that delamination has been a challenge for FRP composites since the 1930s. He stated that conventional FRP composites often have a design life of only 15 to 40 years.
The new material features two primary upgrades to combat this structural weakness. First, the team 3D-prints a thermoplastic healing agent, known as EMAA, directly onto the fiber reinforcement to create a patterned interlayer.
This interlayer makes the laminate two to four times more resistant to delamination from the start. The researchers designed this feature to act like a flexible seam within a stiff structure, making it harder for the material to peel apart under stress.
The second upgrade involves thin, carbon-based heater layers embedded within the composite. When an electrical current passes through these layers, they generate heat to melt the EMAA interlayer.
This process, described by researchers as "thermal remending," allows the melted material to flow into microfractures and re-bond the damaged interface. The composite essentially re-welds itself from the inside using material already present in the structure.
