NRNU MEPhI and BFU named after I. Kanta: Solid lubricant for high-precision equipment

2023: Development of Solid Space Lubricant for Precision Engineering

NRNU MEPhI scientists as part of a scientific group have developed a solid lubricant for high-precision technology that is suitable for working in extreme conditions. According to them, the composition based on tungsten, sulfur and selenium reduces friction several times better than analogues. This was announced on April 24, 2023 by representatives of NRNU MEPHI.

Russia has developed a solid lubricant for space technology

In mechanical engineering, liquid lubricants are usually used. However, they cannot be used in extreme conditions - for example, in spacecraft nodes or inside vacuum manipulators and microelectromechanical devices. Solid lubricants are used for this purpose.

Researchers of NRNU MEPhI in collaboration with colleagues from BFU named after I. Kanta have developed a special solid lubricant with an original nanostructure. It is based on tungsten sulfoselenide with uniformly distributed spherical nanoparticles of pure tungsten.

The lubricant produced is significantly superior to molybdenum or tungsten disulfide or diselenide analogs in efficiency and wear resistance. Scientists managed to choose the optimal combination of "matrix" material and nanoparticles, which allows you to achieve increased hardness and plasticity of the lubricating coating. During friction, a nanofilm (tribofilm) with a thickness of 20 nm is formed on the surface of the coating, which significantly reduces friction due to the weak interaction between atomic planes in its structure, noted one of the authors of the development, the chief researcher of the Department of Solid State Physics and Nanosystems of NRNU MEPhI Vyacheslav Fominsky.

Experiments showed that the friction coefficient for the obtained coatings at room temperature did not exceed 0.02, compared with 0.04-0.07 for analogs.

By changing the sulfur content of the amorphous matrix, it is possible to create high-quality lubricating coatings for difficult operating conditions, such as, for example, with strong cooling of friction units (to -100 ° C) in an inert atmosphere at a low concentration of water vapors, added Vyacheslav Fominsky.

To obtain such coatings of the required structure, scientists used a modernized method of reactive pulsed deposition.

Laser evaporation of tungsten diselenide in hydrogen sulfide was used, which led to the formation of an atomic stream of selenium, sulfur and tungsten and tungsten nanoparticles. The coating was deposited at room temperature of the substrate. The laser deposition method allows flexible adjustment of the composition and structural state of the coatings and opens up the possibility of obtaining materials with super lubricant properties under various conditions. noted scientist.