A research team led by Brian L. Wardle, an associate professor of aeronautics and astronautics at Massachusetts Institute of Technology, has developed a new method to identify internal damage in sophisticated composite materials used in airplanes.
The researchers used a heat-sensitive camera and a simple portable device in the method. The surfaces of sophisticated composite materials such as glass or carbon entrenched in a metal or plastic matrix normally do not cause internal damage when compared to aluminum. However, such composite materials are difficult to check for damage as their surfaces do not show any hidden issues.
To overcome such problems, the composite materials should be developed with carbon nanotubes that produce the required heat for the test. When a small quantity of electric current is used on the surface, the nanotubes heat up and generate radiation that can be sensed by the camera to determine the exact location of damage.
The project led by Wardle is part of a aerospace industry-financed initiative to enhance the mechanical characteristics of current aerospace-grade composite materials. Wardle has collaborated with the US Air Force and Nayv, who have shown significant interest in the new technology. Wardle is currently developing the carbon nanotube hybrid materials for the organizations’ vessels and aircrafts. The new hybrid materials exhibit better mechanical attributes, including toughness and strength, than current sophisticated composite materials.
Infrared thermography is currently used to inspect the internal damage in sophisticated composites. A heat-sensitive camera is used to detect the damages by sensing the infrared radiation released by the heated surface. Any cracks or layer separation in the composite material will redirect the heat flow. However, the main disadvantage of this method is that it requires large heaters to heat the surface.