Sparingly doped eutectic powedery materials and technologies of tribotechnical function coatings with gradient type structure
Sparingly doped alloys based on ferrum of 12Х18Н9Т-ТіВ2, 12Х18Н9Т-СrВ2, 12Х18Н9Т-VС systems have been developed.
Alloys powders mentioned above have been obtained using method of liquid metal sputtering with inert gas flow. Quite thin branched crystals of strengthening phase are formed in the process of crystallization. These crystals create a carcass which armors a metal matrix. Such a structural feature within eutectic colonies as distinct from dispersion-hardened materials allows us to put together different properties of primary components in alloys so that to provide elevated-temperature strength; to change inclusions form and sizes as well as balance of basis mechanical properties and penetration phase; and to influence on tribotechnical properties.
The following technological processes of protective coatings using powders of eutectic alloys have been developed: plasma coating, plasma and laser surfacing, plasma coating with further flashing by high frequency current, laser treatment when complete and discrete flashing and at thermal cycling regime.
The developed coatings are designed with the purpose to replace alloys on nickel basis (which are quite expensive) with cheaper eutectic coatings on steel basis for restoration and machineries service life extension.
Developed eutectic alloys on ferrum basis in comparison with those batch ones on nickel basis are characterized by several practically valuable exploitative features: they are processable, not in short supply, thermally stable, corrosion-resistant, characterized by exclusive tribotechnical properties in a wide temperature range. Performed research proves us that wear-resistance of carbon steels with eutectic coatings is 2-8 higher and more persistent than alloys on nickel basis.