Application industries
The reason for the low service life of blades and other elements of turbine structures is largely related to the damage caused by erosion, which appears during the operation of turbines in the form of cracks, which are the result of stress concentration caused by water droplet erosion. The wear and tear of the inlet and outlet edges of the working blades due to the erosive effect of the steam flow, the appearance of unacceptable defects on the working blades (cracks, point and line through washouts, etc.) lead to the need to replace the working blades, that is, to additional costs.
In recent years, the technology of combined mineral coatings MICOTECH, developed by SPC "Technology of mineral coatings", has been introduced to the market of protective coatings, which is devoid of many disadvantages of known technologies, and the parameters of wear resistance, corrosion resistance, antifriction properties, especially for work in an aggressive environment, significantly exceed the best results created by traditional methods. The technology makes it possible to create wear-resistant mineral coatings on large-sized metal parts without changing their geometry; it does not require special baths, furnaces, and vacuumized space; it does not overheat the part in the process of forming the coating, which eliminates distortions; it is a finishing operation that does not require changing the drawings.
The combination of physical processes of the technology makes it possible to increase the wear resistance of friction pair parts from 3 to 10 (up to 50 times) times compared to traditional methods, allows parts with mineral coating to work at temperatures up to 1300 C, sea water, hydrogen sulfide, abrasive media, high thermal cyclic loads. The technology protects the parts of operating mechanical systems of any purpose against wear and tear, increases their life and reduces energy consumption by maximizing the elimination of mechanical losses in machines and mechanisms.
MICOTECH ® mineral coatings were applied on metal parts, which successfully operate as a part of special equipment of the Russian Navy, floating nuclear power plant "Akademik Lomonosov", Kamchatka (Mutnovskaya) geothermal plant, CHP OAO "Mosenergo".
In view of the fundamental possibility of increasing the wear resistance and corrosion resistance of metal parts working in extreme operating conditions of turbine blades (aggressive air, water, oil, elevated temperature), some enterprises already use MICOTECH ® technology to increase the service life of turbine blades.
The essence of the technological process is the introduction of nanocomposite materials into the metal crystal lattice. The combination of ultradisperse mineral powders and an ultrasonic indenter results in the formation of a nanocomposite surface structure with fragments ordered in composition and dimension, and a controlled, depending on the purpose, change in the mechanical characteristics of the nanocomposite coating material and the main material of the component.
The technology of formation of a mineral coating consists in the process of applying a mineral layer on a surface of a part by means of ultrasonic unit, with simultaneous plastic deformation of surface layers by means of ball or roller knurls, and also the processes protected in a know-how mode. The use of pressing (pressure application) creates the effect of volume compression of the base metal and mineral in the plastic deformation zone, and, as a consequence, the hardening of the surface layer volume. The technology may include electric arc mass transfer of metal microparticles to create a hard-metal cushion.
As a result, nanostructured composites with predicted properties (antifriction, wear-resistant, anti-seize) are formed in the surface layer due to the reduction of the average size of crystallites and the compaction of the base material.
The basic technology serves as the basis for further development of routing and working technologies for different surfaces, parts of different weights and sizes for power engineering.
References:
- Kislov S.V., Kislov V.G., Balasch P.V., Skazochkin A.V., Bondarenko G.G. and Tikhonov A.N. Wear resistance of a metal surface modified with minerals / Materials Science and Engineering, / IOP Conf. Series: Materials Science and Engineering 110 (2016). Electronic access: [http://iopscience.iop.org/article/10.1088/1757-899X/110/1/012096/pdf]
- Kislov S.V., Kislov V.G., Skazochkin A.V., Bondarenko G.G., Tikhonov A.N. Efficient mineral coatings for surface hardening of metal materials / Metals, 2015, № 4, pp.56-63.
- Balash P.V., Kislov S.V., Skasochkin A.V. Small innovative enterprise: opportunities for technology development and business scaling, journal «Innovations», 2015, № 12, pp.95-105.
by SPC Mineral Coating Technologies, LLC with grant support from the Skolkovo Fund.