Obrabotka Metallov. 2017 no. 3(76)

OBRABOTKAMETALLOV № 3 (76) 2017 49 MATERIAL SCIENCE Structure Features of B 4 C-Ni-Р Plasma Coatings Elena Kornienko 1, a,* , Viktor Kuz’min 2, b , Vasiliy Lozhkin 1, с , Igor Gulyaev 2, d , Alexander Sivkov 3, e , Alexander Ivashutenko 3, f , Ilyas Rahmatullin 3, g , Dmitrii Sergachev 2 , h , Viktoriya Bezrukova 1, i 1 Novosibirsk State Technical University, 20 Prospect K. Marksa, Novosibirsk, 630073, Russian Federation 2 Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, 4/1 Institutskaya str., Novosibirsk, 630090, Russian Federation 3 National Research Tomsk Polytechnic University, 30 Lenin Avenue, Tomsk, 634050, Russian Federation a http://orcid.org/0000-0002-5874-5422 , kornienko_ee@mail.ru , b http://orcid.org/0000-0002-9951-7821 , vikuzmin57@mail.ru , c http://orcid.org/0000-0002-1686-0369 , lozhkin@corp.nstu.ru , d http://orcid.org/0000-0001-5186-6793 , gulyaev@itam.nsc.ru , e http://orcid.org/0000-0002-7685-5502 , SivkovAA@mail.ru , f http://orcid.org/0000-0002-6513-5438 , ivaschutenko@mail.ru , g http://orcid.org/0000-0001-5643-2134 , riam@tpu.ru , h http://orcid.org/0000-0003-2469-5946 , yosergach@gmail.com , i http://orcid.org/0000-0002-0329-9920 , vikabezrukova1995@mail.ru ARTICLE INFO Article history : Received: 28 June 2017 Revised: 28 July 2017 Accepted: 15 August 2017 Available online: 15 September 2017 Keywords : Plasma spraying Boron carbide B 4 C-Ni-P Coating Acknowledgements: The research is carried out at Tomsk Polytechnic University within the framework of Tomsk Polytechnic University Competitiveness Enhan- cement Program grant. ABSTRACT Purpose: This paper considers the structural features of B 4 C-Ni-P coatings obtained by air-plasma spraying with the unit for annular injection of powder. Materials and methods: (B 4 C) boron carbide powder clad with 30 wt. % Ni-P is used. The powder is deposited on pipes of low-carbon steel (0.2 % C) by air-plasma spraying with the unit for annular injection of powder. The structure and phase composition of coatings are studied by optical microscopy, scanning electron microscopy with the microanalyser EDS, transmission electron microscopy and X-ray diffractometry. The microhardness measurements results are also presented. Results and discussion: The high-quality composite coatings with low porosity can be formed using plasma spraying. The combination of the optical and scanning electron microscopy as well as X-ray diffractometry revealed the composition of the plasma coatings. It consists of B 4 C particles up to 30 μm sizes that are equally spaced in a metal matrix. The metal matrix consists of nickel borides (Ni 3 B, NiB and Ni 3 B 4 ). Areas with roundish inclusions about 500 nm diameter are surrounded by boron carbide particles. These areas are characterized by a higher content of nickel, phosphorus and boron. B 2 O 3 boron oxide and NiO nickel oxide are also presented in the coating. The microhardness local measurements demonstrated that the microhardness of boron carbide particles is 3000…4000 HV, the metal matrix is 400...550 HV and the areas with roundish inclusions is 200 HV. According to the transmission electron microscopy data thin interlayers with an amorphous-crystalline structure up to 1 μm width are formed between the boron carbide particles and the metal matrix. The metal matrix constitutes areas with a nanocrystalline structure and columnar crystals that located in the coatings volume at random. For citation: Kornienko E.E., Kuz’min V.I., Lozhkin V.S., Gulyaev I.P., Sivkov A.A., Ivashutenko A.S., Rahmatullin I.A., D.V. Sergachev, Bezrukova V.A. Structure features of B 4 C-Ni-Р plasma coatings. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2017. no. 3 (76), pp. 42–50. doi: 10.17212/1994-6309-2017-3-42-50. (in Russian). References 1. Risovannyi V.D., Zakharov A.V., Klochkov E.P., Guseva T.M. Bor v yadernoi tekhnike [Boron in nuclear en- gineering]. Dimitrovgrad, GNTs NIIAR Publ., 2011. 668 p. ISBN 5-9483-016-7. 2. Alekseev A.G., Bovkun G.A., Bolgar A.S., Borisova A.L., Brakhnova I.T., Vinitskii I.M., Gordienko S.P., Go- ryachev Yu.M., Dvorina L.A., Drozdova S.V., Koval’chenko M.S., Kosolapova T.Ya., Kulik O.P., Obolonchik V.A., Paderno Yu.B., Panasyuk A.D., Popova O.I., Rud’ B.M., Serebryakova T.I., Timofeeva I.I., Fomenko V.S. Svoistva, ______ * Corresponding author Kornienko Elena E. , Ph.D. (Engineering), Associate Professor Novosibirsk State Technical University, 20 Prospect K. Marksa, 630073, Novosibirsk, Russian Federation Tel. : 8 (383) 346-11-71, e-mail: kornienko_ee@mail.ru Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2017 no. 3(76) pp. 42–50 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2017-3-42-50 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov