STRUCTURAL-PHASE STATES AND PROPERTIES OF PLASMA SURFACING WITH HIGH-SPEED STEEL IN A NITROGEN ENVIRONMENT

Using the methods of modern physical materials science, studies of the structural-phase states and properties of plasma surfacing from high-speed steel R18Yu in a protective alloying environment of nitrogen were carried out. The main element of the structure of the deposited word is grains, the size of which is 7.0 – 22.5 microns. It has been shown that plasma surfacing with a non-current-carrying flux-cored wire leads to the formation of a layer, the main phases of which are α-Fe and carbides of composition M₆C (M = Fe, W), which form a frame mesh represented by two morphologically different types in the form extended layers and areas with a eutectoid-type structure. The inclusion of the carbide phase does not contain a dislocation sub-structure and is characterized by the presence of flexural extinction contours, which indicates elastic stresses of the surfacing material. The scalar density of chaotically distributed dislocations in α-Fe grains is 2.2∙10¹⁰ cm^–2, and in the network dislocation substructure 1.2∙10¹¹ cm^–2. Using transmission electron microscopy, particles of vanadium carbide of composition V₄C₃ with needle-like morphology were identified in the volume of grains. The crystal lattice parameter (a = 2.888 Å), the size of coherent scattering regions (44 nm) and the carbon concentration in the α-Fe solid solution (0.286 wt.%) were assessed. The microhardness of the deposited layer is 4.7 GPa, the wear parameter is 8.9∙10^–6 mm³/N∙m, the thorn coefficient is 0.7.

1. Malushin N.N., Valuev D.V., Osetkovskii V.L., Solodskii S.A. Technologies for surfac-ing parts of the mining and metallurgical com-plex with high-hardness steels. Tomsk: Izd-vo TPU, 2015:212. (In Russ.).

2. Malushin N.N., Gromov V.E., Romanov D.A., Bashchenko L.P., Peregudov O.A. Hardening of heat-resistant alloys by plasma in nitrogen medium. Novokuznetsk: Poligrafist, 2022:232. (In Russ.). EDN:JUAWCF.

3. Raikov S.V., Kormyshev V.E., Gromov V.E., Ivanov Yu.F., Konovalov S.V. Wear-resistant surfacing on steel: structure, phase composi-tion and properties. Novokuznetsk: ITs Sib-GIU, 2017:318. (In Russ.).

4. Ryabtsev I.A., Senchenkov I.K. Theory and practice of surfacing works. Kyiv: Ekotekhnologіya, 2013:400. (In Russ.).

5. Pokhodnya I.K., Shlepakov V.N., Maksimov S.Yu., Ryabtsev I.A. Research and develop-ment of the E.O. Paton thermal power plant in the field of electric arc welding and surfac-ing with powder wire. Avtomaticheskaya svar-ka. 2010;(12) :34–42. (In Russ.).

6. Vdovin K.N., Nikitenko O.A., Feoktistov N.A., Gorlenko D.A. Study of the effect of ni-trided ferrovanadium on the microstructure parameters of cast Gadfield steel products. Liteishchik Rossii. 2018;(3):23–27. (In Russ.).

7. Nefed'ev S.P., Emelyushin A.N. Plasma-powder sur-facing of nitrogen – containing wear – resistant coat-ings. Vestnik Yugorskogo gosudarstvennogo universi-teta. 2021;(3):33–45. (In Russ.).

8. Kutepov S.N., Kalinin A.A., Gvozdev A.E. Modern steels for high-speed processing of metal alloys. Izvestiya Tul'skogo gosudarstvennogo universiteta. Tekhnicheskie nauki. 2018;(10):597–607. (In Russ.). EDN: JUAWCF.

9. Rakhadilov B.K., Wieleba W., Kylyshkanov M.K., Kenesbekov A.B., Maulet M. Structure and phase composition of high - speed steels. Bulletin of the Karaganda University. Physics Series. 2020;2(98):83–92.

10. https://doi.org/10.31489/2020Ph2/83-92. EDN: ZHOEOP.

11. Kireev V.P. Hardening of high-speed steel by dynamic microalloying and its effect on the wear resistance of cutting tools. Proceedings of the Samara Scientific Center of the Russian Academy of Sciences. 2015;17(6(2)):414–418. (In Russ.). EDN: WDCVAB.

12. Rakhadilov B.K., Zhurerova L.G., Scheffler M., Khassenov A.K. Change in high tempera-ture wear resistance of high speed steel by plasma nitriding. Bulletin of the Karaganda University. Physics Series. 2018;3(91):59–65. EDN: KJWHYN.

13. Ouyang Q., Luo P., Zhang F., He Q., Wang Y., Li S. Analyzing the effect of CeB6 on mi-crostructure and mechanical properties of high-speed steel consolidated by powder met-allurgy. Journal of Materials Engineering and Performance. 2018;27(5):5973–5983.

14. https://doi.org/10.1007/s11665-018-3675-1

15. Ding C.-C., Zhao M.-D., Li Z.-D., Cao Y.-G. Effect of quenching temperature on micro-structure and properties of high-speed axle steel. Transactions of Materials and Heat Treatment. 2018;39(12):49–56.

16. http://dx.doi.org/10.13289/j.issn.1009-6264.2018-0311

17. Rahman N.U., Capuano L., Meer A., Rooij M., Matthews D.T.A., Walmag G., Sinnaeve M., García-Junceda A., Castillo M., Römer G.R.B.E. Development and characterization of multilayer laser cladded high speed steels. Ad-ditive Manufacturing. 2018;24:76–85. https://doi.org/10.1016/j.addma.2018.09.009

18. Matlygin G., Savilov A., Nikolaev A., Timo-feev S. Investigation of form deviations of high-speed steel (HSS) products under turn-ing-milling operation using automatically programmed tools. Science intensive technolo-gies in mechanical engineering. 2023;15–23. https://doi.org/10.30987/2223-4608-2023-7-15-23

19. Petrova L., Sergeeva A., Vdovin V. Modifica-tion of a high-speed cutting tool surface by combined tungsten steel and nitrogen satura-tion. Science intensive technologies in mechan-ical engineering. 2023;24–32.

20. http://dx.doi.org/10.30987/2223-4608-2023-7-24-32

21. Egerton F.R. Physical principles of electron microscopy. Basel: Springer International Pub-lishing, 2016:196.

22. Kumar C.S.S.R. Transmission electron micros-copy. Characterization of nanomaterials. New York: Springer, 2014:717.

23. https://doi.org/10.1007/978-3-642-38934-4

24. Carter C.B., Williams D.B. eds. Transmission electron microscopy. Berlin: Springer Interna-tional Publishing, 2016:518.

25. Ivanov Yu.F., Gromov V.E., Konovalov S.V., Kormyshev V.E., Aksenova K., Teresov A. Structure and properties of strengthening lay-er on Hardox 450 steel. Materials Science and Technology. 2017;33(17):2040–2045.

26. https://doi.org/10.1134/S003602952203003X

27. Konovalov S.V., Kormyshev V.E., Gromov V.E., Ivanov Yu.F., Kapralov E.V. Phase composition and defect substructure of double surfacing, formed with V-Cr-Nb-W powder wire on steel. Inorganic materials: Applied re-search. 2017;8(2):313–317.

28. https://doi.org/10.1134/S2075113317020101

29. Konovalov S.V., Kormyshev V.E., Gromov V.E., Ivanov Yu.F., Kapralov E.V. Gradient structure generated in Hardox 450 steel with built-up layer. Inorganic materials: Applied re-search. 2018;9(3):427–432.

30. https://doi.org/10.1134/S2075113318030164