One of the major contributions that nanotechnology can make in the transportation sector is lighter weight and high strength composite materials (“composites”) for the construction of airplanes and automobiles.
Composites are created from two or more materials with significantly different physical or chemical properties. These properties remain distinct within the finished structure. The promise of nanocomposites is that they will be lighter and stronger than other kinds of widely used composites.
After decades of research and development, composites were first used in civil aviation when Boeing unveiled its 777 airplane in the mid-1990s. Until then, aluminum and other metals were used for airplane bodies. In the next generation of planes (e.g., the Boeing 787 Dreamliner), nearly 50% of the material in use is composites.
Among the leading candidates to become the nanocomposites of choice are Carbon nanotube based nanocomposites and polymer clay nanocomposites. Nanocomposites are expected to offer higher fuel savings to the aerospace industry because of their lighter weight (at strength levels similar or better when compared to those of currently-used materials). The use of nanocomposites also allows for more comfortable journey for airline passengers, since higher cabin pressure and humidity levels are possible; composites suffer less than metals from material fatigue and corrosion.
Some of the other benefits expected from developments in nanotechnology for the aerospace industry are wear-resistant and corrosion-resistant coatings, de-icing coatings, wear-resistant tires, better protection against lightning, sensor networks for monitoring vehicle health, and improved navigation and communication systems.
In the automotive sector, the biggest thrust is to develop alternatives to gasoline and diesel powered engines. Researchers are looking into efficient storage of hydrogen into nanoporous materials that would enable hydrogen powered cars. Other nano-enabled benefits in the automotive sector include high strength and light weight components, paintable polymers, anti-fouling paints, ultraviolet light (UV) protective coatings, corrosion protection, and organic light emitting diodes (LEDs) for panel lighting and instrumentation.
Many transportation applications use multifunctional material. While the major function of the structure is often load-bearing, additional properties of the material are desirable. Such properties involve: electrical characteristics (conducting or insulating); thermal characteristics (conducting or insulating); health effects (monitor, control); sensing (physical variables such as stress, strain); reaction to environmental effects (ice, rain, contaminants); stealth (managing or suppressing electromagnetic or visible radar signatures); and actuation.