State in the Field of Heat-Resistant Coatings for Heat-Proof Nickel Alloys and Steels

Abstract

Currently, in many industries, special attention is paid to increasing the reliability and economy of the products. Solving problems requires the use of materials that can work in difficult conditions, which determines the relevance of the problem stated in the article. The purpose of the article was to conduct a critical analysis of coatings developed in Russia that are diverse in composition, technological and operational properties, from the standpoint of the possibility of using them to provide a reliable material protection system under conditions that cause high-temperature gas corrosion and surface layer erosion. The main methods of materials protection were considered in the work: thermal spraying, plasma spraying, electron beam, plasma electric arc cathode spraying, vacuum deposition, chemical-thermal treatment, diffusion coating based on aluminum. Among the more effective methods, the method of self-propagating high-temperature synthesis, the method of high-energy plasma chemistry, the methods of physical deposition in vacuum are noted. The types of coatings were also highlighted and their short characteristics were given. Particular attention was paid to heat-resistant coatings based on refractory enamels since their advantages include low cost and the possibility of applying them directly to parts. A number of technical solutions have been identified that protect the alloys from high-temperature gas corrosion and erosion under long-term operation in aircraft products at high temperatures. The results of the article may be useful for further research since individual developments are uninformative from the standpoint of solving specific problems and require expensive bench testing of the claimed technical result.

High Temperature Coatings for Oxidation and Erosion Protection of Heat-Resistant Carbonaceous Materials in High-Speed Flows

“…5. The method of coating with pastes and slurries (slip-roasting) allows to apply coatings [31,33,[108][109][110][111][112] on parts of complex shape and has a low cost, but this technology requires a relatively high temperature heat treatment to obtain dense coatings, which, in turn, can cause damage to CCM [113]. In recent years, the production of protective coatings is increasingly achieved by combining several traditional technologies.…”

“…Currently, there are various methods to protect CCM from exposure to oxygen-containing environments, including: − management of carbon structure and use of its various modifications [11][12][13]; − inhibition of composites matrix by antioxidants [14][15][16][17][18][19]; − application of heat-resistant coatings on reinforcing fibers [20][21][22]; − application of coatings on surfaces in contact with oxidizing environments [21,[23][24][25][26][27][28][29][30][31][32].…”

Half-timbered houses of the Tudor and Elizabethan periods in Britain

“…Places for conveniences were arranged outside the house, in the backyard. Usually, they washed inside the house, for which each bedroom had individual hygienic devices -jugs with basins for bathing, night pots, sometimes enclosed in a "transformer throne" and others [121][122][123][124][125][126].…”

Studying microstructure of heat-resistant alloy based on the Fe-Cr-Ni-alloying element system for manufacture of components for metallurgical equipment

“…The durability of the components made of these steels is low and makes 3-4 months in average, then it is necessary to replace them, which leads to equipment downtime and reduced productivity. The reason for the short life of the parts is relatively low heat resistance of steels they are made of [6][7][8][9][10]. An alternative to heat-resistant steels are heat-resistant alloys based on Cr-Ni or Ni-Co systems.…”