According to MIT News, aerospace engineers at MIT have found a way to bond composite layers in a way that the resulting composite material is substantially stronger and more damage-resistant than other advanced composites. Roberto Guzman, an MIT postdoctoral student who led the work, said the resulting composites could drastically improve airplane parts.
“More work needs to be done, but we are really positive that this will lead to stronger, lighter planes,” says Guzman, who is now a researcher at the IMDEA Materials Institute in Spain. “That means a lot of fuel saved, which is great for the environment and for our pockets.”
As MIT’s article explains, Guzman and his team fastened layers of composite materials together using incredibly strong carbon nanotubes. They embedded tiny “forests” of carbon nanotubes within a glue-like polymer matrix, then pressed the matrix between layers of carbon fiber composites. The nanotubes, which look like vertical stitches, worked themselves within the crevices of each composite layer, serving as a scaffold to hold the layers together.
In experiments to test the material’s strength, the team found that, when compared with common composite materials, the stitched composites were 30 percent stronger and withstood greater forces before breaking apart. MIT professor Brian Wardle, the study’s co-author, attributes that to the size of the materials. Wardle says carbon nanotubes are only about 10 nanometers in diameter — nearly a million times smaller than the carbon fibers.
“Size matters, because we’re able to put these nanotubes in without disturbing the larger carbon fibers, and that’s what maintains the composite’s strength,” Wardle says. “What helps us enhance strength is that carbon nanotubes have 1,000 times more surface area than carbon fibers, which lets them bond better with the polymer matrix.”
To read the whole study, Interlaminar and intralaminar reinforcement of composite laminates with aligned carbon nanotubes, click here.