Orenburg State University, Orenburg, Russia:

S. E. Krylova, Dr. Eng., Prof., Dept. of Materials Science and Technology, e-mail: krilova27@yandex.ru
A. Yu. Plesovskikh, Postgraduate student, Aerospace Institute
I. A. Kurnoskin, Postgraduate student, Aerospace Institute
I. Sh. Tavtilov, Cand. Eng., Associate Prof., Dept. of Materials Science and Technology

The influence of heat treatment modes on the structure and properties of the Ni – Cr – B – WC coating system applied by GDCS (cold flame spraying) on the working part of the Compressor Rod product of oil and gas equipment has been revealed. The optimal quenching mode for tungsten coating on AISI 4140 steel is recommended, including heating to temperatures of 1150 °C, exposure, followed by rapid cooling in a water-polymer medium. Using optical and scanning electron microscopy (SEM), the features of the formation of the structure and distribution of the carbide phase in the coating are determined. According to the structural analysis, after heat treatment, partial recrystallization of the binding components (Ni) occurs, redistribution of hardening particles (WC, Cr, B), which leads to a change in the structure and dispersion of the sprayed surface layer of the product. It is established that, depending on the parameters of heat treatment and further local remelting, an increase in interplate cohesion, a decrease in porosity, and a decrease in the microhardness of the coating base on average by 20 % of the initial value is observed, characteristic of this process. Recrystallization processes at the stage of heat treatment of the alloyed coating increase wear resistance despite a decrease in hardness. The achieved results make it possible to predict the possibility of using such products after heat treatment in a friction pair with increased requirements for wear resistance and adhesive strength.

1. Plesovskikh А. Yu., Krylova S. Е., Oplesnin S. P. Import-substituting technology for manufacturing parts for the oil and gas industry with the application of tungsten-based wear-resistant coatings. Vestnik sovremennykh tekhnologiy. 2019. No. 2 (14). pp. 9–14.
2. Plesovskikh A. Y., Oplesnin S. P., Kurnoskin I. A., Krylova S. E. Import-substituting technology for manufacturing parts of the oil and gas industry with the application of tungsten- based wearresistant coatings. Materials Today: Proceedings. International Conference on Modern Trends in Manufacturing Technologies and Equipment 2020, ICMTMTE 2020. 2021. pp. 1595–1598.
3. Plesovskikh А. Yu., Krylova S. Е. Import-substituting technology for manufacturing parts of the oil and gas industry with the application of tungsten-based wear-resistant coatings. Physical materials science. Actual issues of strength : proceedings of the X International School dedicated to the 10^th anniversary of the laboratory "Strength Physics and Intelligent Diagnostic Systems" and LXIII International Conference. Tolyatti, 2021. pp. 56, 57.
4. Kornienko Е. Е., Nikulina А. А., Bannov А. G. et al. Influence of reflow temperature on the structure and properties of nickel-based self-fluxing coatings. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty). 2016. No. 4 (73). pp. 52–62.
5. Gonzalez R., Cadenas M., Fernandez R., Cortizo J. L., Rodriguez E. Wear behaviour of flame sprayed NiCrBSi coating remelted by flame or by laser. Wear. 2007. Vol. 262. pp. 301–307.
6. Rong Hu, Jun Zhang, Ruidong Wang, Chao Zhang, Zixin Xie, Yuwen Zhang, Guangshi Li, Xionggang Lu. Effect of heat treatment on microstructure and properties of WC reinforced co-based composite coating on copper. Materials Letters. 2022. Vol. 319. 132262.
7. Ghadami F., Heydarzadeh Sohi M., Ghadami S. Effect of bond coat and post-heat treatment on the adhesion of air plasma sprayed WC – Co coatings. Surface and Coatings Technology. 2015. Vol. 261. pp. 289–294.
8. Deenadayalan K., Murali Vela, Elayaperumal A., Satheesh Kumar A., Arulvel S., Mehdi Shahedi Asl. Friction and wear properties of short time heat-treated and laser surface re-melted NiCr – WC composite coatings at various dry sliding conditions. Journal of Materials Research and Technology. 2022. Vol. 17. pp. 3080–3104.
9. Shi-Hong Zhang, Tong-Yul Cho, Jae-Hong Yoon, Wei Fang, Ki-O Song, Ming-Xi Li, Yun-Kon Joo, Chan Gyu Lee. Characterization of microstructure and surface properties of hybrid coatings of WC – CoCr prepared by laser heat treatment and high velocity oxygen fuel spraying. Materials Characterization. 2008. Vol. 59, Iss. 10. pp. 1412–1418.
10. Serres N., Hlawka F., Costil S., Langlade C., Machi F. An investigation of the mechanical properties and wear resistance of NiCrBSi coatings carried out by in situ laser remelting. Wear. 2011. Vol. 270, Iss. 9–10. pp. 640–649.
11. Genga R. M., Cornish L. A., Akdogan G. Effect of Mo2C additions on the properties of SPS manufactured WC–TiC–Ni cemented carbides. International Journal of Refractory Metals and Hard Materials. 2013. Vol. 41. pp. 12–21.
12. Fen Е. К. Wear- and heat-resistant coating materials for supersonic plasma and electric arc spraying. Svarshchik: tekhnologii, proizvodstvo, servis. 2011. No. 1. pp. 32–35.
13. Plesovskikh А. Yu., Krylova S. Е., Oplesnin S. P. Development of a metallurgical powder composition for the restoration of parts in the oil and gas industry. Ural School of Young Metallurgists: proceedings of the XX International scientific and technical Ural school-seminar of metallurgists-young scientists, Ekaterinburg, February 3–7, 2020. pp. 504–507.
14. Bradai Mohand A., Bounar N., Benabbas A., Ati A. Study of microstructure, phases and microhardness of metallic coatings deposited by flame thermal spray. Journal of Materials Processing Technology. 2008. Vol. 200. Iss. 1–3. pp. 410–415.
15. GOST 9450–76. Measurements microhardness by diamond instruments indentation. Introduced: 01.01.1977.
16. Goncharov А. N., Kolmykov D. V., Goncharova Е. V. Modern materials for thermal spraying. Scientific support of agro-industrial production: proceedings of the International Scientific and Practical Conference, Kursk, 25–27 January, 2012. Part 3. pp. 227–230.
17. Chernovol М. I., Vorona Т. V., Shtempel О. P., Lopata L. А. The use of structural-phase transformations and modification during electrocontact processing of steel gas-thermal coatings to increase the wear resistance of agricultural machinery parts. Vestnik Polotskogo gosudarstvennogo universiteta. Seriya V. Promyshlennost. Prikladnye nauki. Mashinovedenie i mashinostroenie. 2016. Iss. 3. pp. 115–122.