Stealth technology has proven to be one of the effective approaches to enhance the survivability of Aircrafts. Aircraft/helicopter designers are making them stealthier by reducing their signatures; viz. visual, aural, infrared (IR), and RADAR cross section. Advancements in stealth technologies, as demonstrated by the very low RCS of stealth aircraft such as F-117, B-2 and F-22, make such targets extremely difficult to detect. At present, stealth aircraft mainly rely on special geometry – their body shape – to deflect radar signals, but those designs can affect aerodynamic performance.
Therefore militaries employ Microwave absorbers, a kind of material that can effectively absorb incident microwave energy to effectively reduce the radar cross sections and radar dectability and hence commonly used in aircrafts and warships for stealth missions. In 2006 researchers demonstrated it was possible to absorb or direct electromagnetic waves around an object through a coating and make it “invisible”. However, it only worked on microwaves and in two dimensions.
The need for microwave absorbers and radar absorbing materials and structures (RAM and RAS) is continuously growing for military applications (e.g., reduction of radar signature for aircraft, ships, tanks, and other mobile objects) as well as in many civilian applications (EM interference shielding, reduction of reflected radiation from microstrip radiators, anechoic chambers, and human exposure mitigation, etc.).
Radar-absorbing material (RAM)
Radar-absorbing material (RAM) is a specialist class of polymer-based material applied to the surface of stealth military aircraft, such as the F-22 Raptor and F-35 Lightning II, to reduce the radar cross-section and thereby make them harder to detect by radar. These materials are also applied in stealth versions of tactical unmanned aerial systems, such as the Boeing X-45. RAM is applied over the entire external skin or (more often) to regions of high radar reflection such as surface edges. RAM works on the principle of the aircraft absorbing the electromagnetic wave energy to minimise the intensity of the reflected signal.
Information about the composition of RAMs is guarded by the military. Most RAMs consist of ferromagnetic particles embedded in a polymer matrix having a high dielectric constant. One of the most common RAMs is called iron ball paint, which contains tiny metal-coated spheres suspended in an epoxy-based paint. The spheres are coated with ferrite or carbonyl iron. When electromagnetic radiation enters iron ball paint it is absorbed by the ferrite or carbonyl iron molecules which causes them to oscillate. The molecular oscillations then decay with the release of heat, and this is an effective mechanism of damping electromagnetic waves. The small amount of heat generated by the oscillations is conducted into the airframe where it dissipates.
Another type of RAM consists of neoprene sheet containing ferrite or carbon black particles. This material, which was used on early versions of the F-117A Nighthawk, works on the same principle as iron ball paint by converting the radar waves to heat. The USAF has introduced radar-absorbent paints made from ferrofluidic and nonmagnetic materials to some of their stealth aircraft. Ferrofluids are colloidal mixtures composed of nano-sized ferromagnetic particles (under 10 nm) suspended in a carrier medium. Ferrofluids are superparamagnetic, which means they are strongly polarised by electromagnetic radiation. When the fluid is subjected to a sufficiently strong electromagnetic field the polarisation causes corrugations to form on the surface. The electromagnetic energy used to form these corrugations weakens or eliminates the energy of the reflected radar signal. RAM cannot absorb radar at all frequencies. The composition and morphology of the material is carefully tailored to absorb radar waves over a specific frequency band.
However, the application of the absorbers invariably requires weight reduction for energy efficiency and capability of operation at broad bandwidth. Polymer composites comprised of a carbonaceous material filled into a polymer matrix also offer large flexibility in complex design and tunable property via choice of the type of carbonaceous inclusions (e.g., C black, CNT, carbon fiber and CNF, graphene, graphene oxide) and the embedding polymer matrix (either rubbers or thermoplastics).
Researchers have now turned to Metamaterials to solve these challenges. Metamaterials are artificially structured materials designed to control and manipulate physical phenomena such as light and other electromagnetic waves, sound waves and seismic waves in unconventional ways, resulting in exotic behavior that’s not found in nature. Researchers have shown that metamaterials formed by resonant metallic structure printed on a dielectric substrate acts as a strong resonant absorber, and such a metamaterial absorber is significantly thinner than the wavelengths absorbed. Research on active frequency selective surfaces (AFSSs) shows that a frequency selective surface (FSS) loaded with lumped elements, such as varactors and PIN diodes, can exhibit a tunable absorption bandwidth.
Stealth Coating market
Stealth Coating Market size was valued at around USD 593 million in 2019 and will exhibit a growth rate of over 6.5% from 2020 to 2026. Rising applications of stealth coatings in military weapons, submarines, and vehicles are projected to offer new opportunities to the overall market growth.
Stealth coatings consist of high concentrations of iron powders in a polymer matrix. Thermoplastic materials, such as epoxy, polyimide, PEEK, PPS, PES, isocyanate, and polyetherimide, have become ideal materials for stealth coatings. Stealth coatings are used in aircraft and military weapons. Additionally, they are also applied to many other surfaces including phone screens, computer & tablet screens, and cars, among others.
Furthermore, rising applications of stealth coatings in cars for UV protection and protection from chips, scratches, road debris, & malicious damages are further projected to propel the industry growth. Increasing smartphone production across the globe is also expected to spur the demand for stealth coatings. Additionally, newer applications of stealth coatings in foods and drugs are anticipated to offer new growth opportunities to the global stealth coating market.
Increasing investments in the aerospace & defense industry, especially in China, India, and Russia, are anticipated to boost the adoption of stealth coatings. Additionally, the growing penetration of stealth coatings in developing economies, such as India, China, Brazil, and South Africa, is also projected to propel the global stealth coating market growth.
Rise in epoxy stealth coatings demand and increase in application from the aerospace & defense industry drive the growth of the global stealth coating market. However, high cost of investment restrains the market growth. Contrarily, surge in investment in R&D for stealth technology creates new opportunities in the next few years.
Because of COVID-19 , Manufacturing activities of stealth ships, aircrafts, and drones has been restricted to the significant extent due to the lockdown measures taken by the governments of various countries including Russia, China, and others. Furthermore, manufacturers of the fifth-generation stealth fighter aircraft halted their manufacturing activities, which in turn, led to lowered demand for stealth coating.
The increasing aircraft demand along with technological innovations is further anticipated to boost the overall stealth coating market growth. However, the Boeing Market Outlook (BMO) 2020 projects that the commercial aviation and services markets will face significant challenges due to the pandemic, while the global defense services market will remain stable.
The growing demand for innovative coatings in the aerospace industry with unique properties suitable for military aircraft will positively contribute to the overall market. Major players such as Intermat Defense are constantly investing in research and development for product innovations with excellent characteristics. Furthermore, the rise in demand for stealth coating applications in smartphones is also anticipated to support the global stealth coating market growth.
The aerospace & defense segment will account for around 37% share in the global stealth coating market in 2026. The surging aircraft production in the U.S., China, and Russia is one of the major factors driving the business growth. Stealth coating is widely used in military aircraft, such as the F-35 Lightning II and F-22 Raptor, to reduce radar cross-section, thereby making them difficult to detect by radars.
Aircraft manufacturers, such as Boeing and Airbus, are largely adopting stealth technology in aircraft production, enhancing the consumption of stealth coatings. Additionally, emerging applications of stealth coatings in luxurious cars for UV protection and better appearance will further influence the overall stealth coating market price. It also protects cars from chips, scratches, road debris, and malicious damage.
The epoxy segment to maintain its leadership status during the forecast period
By resin type, the epoxy segment accounted for the highest market share, contributing to nearly half of the global stealth coating market in 2019, and is estimated to maintain its leadership status during the forecast period.
Epoxy is the largest segment that accounted for around 45% share in the global stealth coating market in 2019 and will grow at a CAGR of over 6.8% from 2020 – 2026.This is due to increase in applications in the aerospace & defense and automotive sectors along with its properties such as strength, durability, and chemical resistance.
Growth is majorly attributed to the growing usage of epoxy stealth coating in aircraft and cars owing to its numerous advantages including cost efficiency and excellent protection against corrosion. The polyurethane segment is anticipated to observe substantial growth in the coming years. Polyurethane coatings offer superior properties such as toughness, chemical resistance, and provides excellent adhesion to all substrates.
However, the polyurethane segment is expected to manifest the highest CAGR of 5.8% from 2020 to 2027, owing to growth of the automotive industry and surge in demand and production of luxurious cars across the developing countries such as India and China.
North America dominated the global stealth coating market and shall account close to 40% demand share in 2026 owing to the growing aircraft production, especially in the U.S., and rising consumption of stealth coatings in luxurious cars. To protect their manned and unmanned aircraft from enemy radar, the U.S. military and its allies are increasingly becoming dependent on stealth technology.
Additionally, the U.S. has more deliveries of jet fighters than China and Russia combined and owns fifth-generation stealth fighters. Furthermore, the surging applications of stealth coatings in military aircraft in European countries, especially in Russia, are further projected to boost the consumption of stealth coatings in the region.
Asia Pacific is expected to grow significantly owing to the emerging applications of these coatings in vehicles and smartphones. The rapid surge in aircraft production, mainly in, China is also one of the key factors boosting the Asia Pacific stealth coating market.
Key players in the stealth coating industry are primarily focusing on product innovations and strategic alliances, such as partnerships, collaborations, & joint ventures, to hold a large market share in the industry. The market is consolidated with the presence of a few players and has a moderate barrier level for new entrants due to stringent regulations and high capital investments.
Key players in the stealth coating industry are majorly focused on offering innovative products with enhanced functionalities. Major players are expanding their presence in emerging countries to cater to the increasing demand for stealth coatings in cars and the aerospace industry. The key manufacturers of stealth coatings include Intermat Defense, CFI Solutions, Hyper Stealth Technologies Pvt. Ltd., Stealth Coatings Inc., Micromag, Veil Corporation, and Stealth Veils, among others.
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