Purpose. The reliability of the operation of machines and mechanisms is determined primarily by the qualitative condition of the working surfaces of parts purposefully formed during the finishing operations of technological processes (geometric accuracy, macro- and microgeometry, physical and mechanical properties of the material, stress-strain state of the surface layer). The creation of fluoroplastic composite coatings on a metal matrix on working surfaces makes it possible to successfully solve the problem of creating friction surfaces with a certain set of necessary operational parameters in terms of reliability, wear resistance, contact endurance and fatigue strength, and the use of thin fluoroplastic coatings is a very promising direction. -mechanical properties of mating surfaces
Specifications. Analysis of the obtained results showed that the resistance of fluoroplastic coatings based on F-30P to damage to the scraper with an increase in the content of C-1 graphite from 15 to 25 wt. % increases by 2.11 times, and when introduced to a coating containing 25 wt. % graphite C-1 additional 3 wt. % aminoorganic silica based on Aerosil – 3.16 times. Additional heat treatment of these coatings results in a 30% increase in resistance to scraper damage. It has been established that when a three-layer fluoroplastic coating based on F-30 P is introduced into the outer layer of 17 wt. % graphite C-1+1 wt. % aminoorganosilica based on aerosil and +2 wt. % ZrO2 +3% Y2O3 (500 °C) or 2 wt. % ZrO2 +3% Y2O3 (700 °C) or 2 wt. % amorphous zirconium hydroxide doped with yttrium ions (the amount of yttrium in terms of oxides is 3 mol%): Zr(Y)O(OH)2 abrasive resistance of the coating increases by 1.38, 1.57 and 1.83 times, respectively
Application area. Enterprises of mechanical engineering and light industry of Ukraine.
Advantages. The method of applying coatings from powder materials in an electrostatic field has significant advantages over all of the above methods: – no preheating; – reduction of losses of powder material; – the possibility of obtaining coatings of uniform thickness on products of complex configuration; – the ability to automate the spraying process; – versatility and high performance; – environmental cleanliness; – minimizing fire and explosion hazards. These factors determined the widespread use of technology for applying polymer coatings in an electrostatic field.
Technical and economic effect. The proposed fluoropolymer coatings make it possible to extend the service life of process equipment by increasing the wear resistance of parts by 40%. Operating costs for the composite material and its application to the surface, depending on the shape and area of the part, are 7-15%. Thus, the technical and economic effect of using a fluoropolymer coating will be about 25% of the cost of the part on which the composite is applied. In addition, the use of fluoropolymer coating makes it possible to replace stainless steel and non-ferrous metals (brass, bronze, etc.) with carbon steel, which is important for food and chemical industries. In this case, due to the difference in the cost of materials, the economic effect will be about 100% of the cost of an element of equipment, a part coated with a composite.
Description. Surface preparation by cold phosphating, electrostatic spraying of the coating onto the prepared surface, followed by its melting according to the established temperature-time regime. The coating is a fluoroplastic F-30P modified with zirconium oxide nanopowders and amino-organosilica (SiO2). The technology provides an increase in performance indicators: adhesive strength by 3.16 times and abrasive wear resistance by 1.83 times.