The aerospace industry is one of the most important heavy industries in the world. Countless companies rely on the ability to ship products and people around the world with the speed that can only by achieved by air.
Along with this huge economic value, however, comes huge consumption, and one of the largest carbon footprints on the planet relative to the size of the market. For this reason, the major drivers in current aerospace R&D are towards lighter construction materials and more efficient engines – the overall goal being to reduce fuel consumption and carbon emissions associated with air travel and air freight. The significant interest in nanotechnology for the aerospace industry is justified by the potential of nanomaterials and nanoengineering to help the industry achieve this goal.
Nanotechnology is defined as the study and the use of structures smaller than 100 nanometers. This technology is capable of transforming the ways in which materials are produced, and the functionalities of the same can be retained or augmented. The drive for lighter and more efficient air vehicles has led to the rapid adoption of nanotechnology in aerospace manufacturing.
The aerospace applications for nanotechnology include high strength, low weight composites, improved electronics and displays with low power consumption, variety of physical sensors, multifunctional materials with embedded sensors, large surface area materials and novel filters and membranes for air purification, nanomaterials in tires and brakes and numerous others.
Primarily, there are three types of nanomaterials employed in aerospace manufacturing; nanostructured metals, polymer nanocomposites, and anti-corrosion coatings. The use of nanotechnology or nanomaterial ensures that an airborne platform retains its operational superiority, enhances the physical properties of structural and non-structural polymers used in the construction of an aircraft, and deliver efficient nano and micro sensors used in spacecraft.
The resultant components also prevent corrosions, thereby increasing the longevity of the platform. Technavio anticipates that the use of nanotechnology will reflect long-term sustainability and ensure enhancement in the overall performance of an aircraft/spacecraft.
Bulk metals with some nanoscale structure are already widely used in aircraft manufacturing. It is now well known that nanostructured metals – exhibit considerably improved properties compared to their counterparts with microscale or larger grain structure.
This is particularly noticeable for properties which are crucial for materials used in aircraft – primarily yield strength, tensile strength and corrosion resistance, coupled with low density which helps keep the total weight of the aircraft down.
Various nanomaterials have been used as filler materials to enhance the properties of structural and non-structural polymers used in aircraft construction. The most commonly used nanomaterials include nanoclays, carbon nanotubes, nanofibres, and graphene.
Carbon nanotubes in particular have been shown to give excellent advantages when used as fillers in various polymers, due to their exceptional stiffness, toughness, and unique electrical properties.
Nanocomposites typically have superb weight-to-strength ratios, and enhanced resilience to vibration and fire, making them ideal for use in the aviation industry. The properties of the nanofillers, like the conductivity of nanotubes, for example, can create interesting opportunities for multifunctional materials.
Boeing announced its investment in Gamma Alloys, which specializes in aluminum alloys focused on developing advanced metal-matrix composites for use in aerospace, automotive and other industries. According to prnewswire.com, Gamma Alloys is pursuing breakthroughs in nano-reinforced aluminum alloys, where the aluminum is reinforced with microscopic particles, or nanoparticles. These alloys provide increased stiffness, improved wear resistance, and greater strength than current materials across a wider range of temperatures.
The properties of polymers enhanced by nanomaterial fillers are so well-tuned to the requirements of aircraft manufacturers, that they are actually being used to replace some of the metals used in the airframes. This obviously brings along huge weight savings, and often cost savings as well.
Tribological and Anti-Corrosion Coatings
Another major trend in the materials used in aircraft is towards nanocoatings to enhance the durability of metals. In particular, magnesium alloys, which are far lighter than steel or aluminium, are prone to corrosion, due to the high chemical reactivity of magnesium. Coatings can help prevent corrosion, but the type typically used contain chromium complexes which are a highly toxic pollutant.
Materials used for these novel anti-corrosion nanocoatings include silicon and boron oxides, and cobalt-phosphorous nanocrystals.
Nanocoatings are also now being used on turbine blades and other mechanical components which have to withstand high temperatures and friction wear. Tribological coatings can drastically lower the friction coefficient and improve resistance to wear – this greatly improves the efficiency of the engines.
Researchers at University West in Sweden have started using nanoparticles in the heat-insulating surface layer that protects aircraft engines from heat. In tests, this increased the service life of the coating by 300%. To increase the service life of aircraft engines, a heat-insulating surface layer is sprayed on top of the metal components. Thanks to this extra layer, the engine is shielded from heat. The temperature can also be raised, which leads to increased efficiency, reduced emissions, and decreased fuel consumption. “The base is a ceramic powder, but we have also tested adding plastic to generate pores that make the material more elastic,” says Nicholas Curry.
Many nanostructured and nanoscale coating materials have been suggested as possible friction modifying agents, such as carbides, nitrides, metals, and various ceramics.
Global Nanotechnology growth for Aircraft Market
Market analysts forecast the global aerospace nanotechnology market to grow at a CAGR of 5.75% during the period 2017-2021.
The latest research report also encloses key features contributing to the development of the global Nanotechnology Enabled Coatings for Aircraft market.
Also, key product categories, segments Anti-corrosion, abrasion, and wear-resistant aircraft nanocoating, Thermal barrier and flame retardant aircraft nanocoating, Anti-icing aircraft nanocoating, and sub-segments Commercial aircraft, Military aircraft are involved in the global Nanotechnology Enabled Coatings for Aircraft market report.
AnCatt, Applied Thin Films, FlightShield, Glonatech, Triple, CHOOSE NanoTech, General Nano, HR ToughGuard, Surfactis Technologies, Tesla NanoCoatings are dominating players in the global Nanotechnology Enabled Coatings for Aircraft market.