Prabhat Ranjan Mishra – IE
Stealth coatings have been essential for fighter jets to minimize their detection, even if adversaries use multiple detection methods.
However, producing stealth materials has never been cost-effective. Now, scientists in China have developed a method to produce these coatings at a low cost.
The method uses iron to save costs and achieves both radar and infrared stealth.
Stealth coating developed using ordinary industrial equipment
Led by Jiang Fan, a scientist from the Naval Equipment Department, the research team developed the stealth coating using ordinary industrial equipment such as a laser processing machine.
They claimed that they used metallic iron, which is cheap and has a simple preparation process, to prepare radar– and infrared-compatible stealth coatings.
Stealth coating reduces thermal signature of planes
The stealth coating not only reduces the thermal signature of aircraft but also absorbs and converts radar waves into heat.
The outermost layer of the coating is made from pure iron film that is just 100 nanometers thick. Commercial magnetron sputtering equipment, which is commonly used to coat frames for spectacles, can be used to prepare this film, according to SCMP.
The film’s outermost layer is composed of pure iron, while the secondary layer beneath it comprises resin infused with carbonyl iron flakes.
Carbonyl iron powder is a typical magnetic absorbing material
According to researchers, carbonyl iron powder is a typical magnetic absorbing material that has been widely used because of the advantages of high permeability, low dispersion effect in real and imaginary parts of permeability, and strong absorption efficiency under low matching thickness.
The composites exhibited excellent thermal stability, with changes in complex permittivity and permeability remaining less than 7% even after being heated at 446°F (230°C) for 10 hours. The microwave absorption performance of the material could be further improved, according to the study.
Coating efficiently absorbs electromagnetic waves
The research team found that the coating efficiently absorbs electromagnetic waves. During the laboratory tests, it also reduced the intensity of infrared signals by more than 80%. This capability could help the coating to bypass any air defense system, according to the research.
While the paper details a large number of parameters used in the production process, such as laser power and pulse frequency, the researchers have omitted some key information, including the pattern of the laser-etched microstructure, so other countries cannot replicate the material, reported SCMP.
Earlier, researchers in China developed a coating that effectively decreases infrared signal intensity by 80%. However, that material used expensive metals, including gold and platinum.
