Obrabotka Metallov 2020 Vol. 22 No. 2

OBRABOTKAMETALLOV Vol. 22 No. 2 2020 114 MATERIAL SCIENCE References 1. Okovity V.A., Panteleenko A.F. Optimizatsiya protsessa napyleniya iznosostoikikh pokrytii na osnove mnogofunktsional’noi oksidnoi keramiki [Optimization of the deposition process of wear-resistant coatings based on multifunctional oxide ceramics]. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2015, no. 2, pp. 46–54. DOI: 10.17212/1994-6309-2015-2-46-54. (In Russian). In fl uence of Thermal Effects on the Micromechanical Properties of the Nickel-Chromium Coating obtained by Gas Powder Laser Cladding Natalia Soboleva 1, a,* , Aleksey Makarov 1, 2, 3, b , Alexander Stepchenkov 1, 2, c , Irina Malygina 1, d , Yury Korobov 2, 3, e 1 Institute of Engineering Science, Ural Branch of the Russian Academy of Sciences, 34 Komsomolskaya st., 620049, Ekaterinburg, Russian Federation 2 M.N. Miheev Institute of Metal Physics, Ural Branch, Russian Academy of Sciences, 18 So fi a Kovalevskaya st., Yekaterinburg, 620219, Russian Federation 3 Ural Federal University named after the fi rst President of Russia B.N. Yeltsin, 19 Mira st., Yekaterinburg, 620002, Russian Federation a https://orcid.org/0000-0002-7598-2980, natashasoboleva@list.ru, b https://orcid.org/0000-0002-2228-0643, avm@imp.uran.ru , c https://orcid.org/0000-0001-9431-0170 , alexander.stepchenkov@gmail.com , d https://orcid.org/0000-0002-9463-1473 , malygina@imach.uran.ru, e https://orcid.org/0000-0003-0553-918X , yukorobov@gmail.com Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2020 vol. 22 no. 2 pp. 104–117 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2020-22.2-104-117 Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov ARTICLE INFO Article history : Received: 21 March 2020 Revised: 20 April 2020 Accepted: 11 May 2020 Available online: 15 June 2020 Keywords : Laser cladding Nickel-chromium coating Thermal action Instrumental microindentation Scanning electron microscopy Funding The work was supported by RSF, grant No. 19-79-00031. The research was done on the equipment of the Plastometriya collective use center, IES UB RAS. ABSTRACT Introduction . Nickel-chromium coatings can be used in parts that are operated at high temperatures (hot defor- mation dies, rolls of rolling mills, live rolls, parts of turbines, heat exchangers, etc.). A promising method of coating deposition is gas powder laser cladding, which forms coatings with increased hardness and uniformity. A modern method for evaluating the mechanical properties of nickel-chromium coatings is instrumental microindentation, which records diagrams during loading and unloading of the indenter. The aim of the work is to study the effect of thermal action in the temperature range of 800…1050 °C on the micromechanical properties of the NiCrBSi coating PG-10N-01 obtained by gas powder laser cladding. Methods of research are instrumental microindentation and scanning electron microscopy using energy-dispersive microanalysis. Results and discussion. Thermal action at a temperature of 800 °C only slightly reduces the strength characteristics of the coating, while the dissolution of the strengthening phases in the structure of the coating when heated to 900 °C leads to a signi fi cant decrease in the hard- ness characteristics and parameters that characterize the resistance to elastic-plastic deformation. The formation of a “frame-like” structure with a base of large carboborides Cr2(B,C) and borides Cr2B with increased elastic moduli upon heating to 1050 °C (holding for 1 h, cooling in air) leads to a strong increase in the average contact elastic modulus to ~ 280 GPa (with an average level of elastic modulus of ~ 200 GPa in the coating after cladding and after additional heating to 800 and 900 °C). Also, the strength characteristics of microindentation (Martens hardness and indentation hardness at maximum load) and calculated parameters that indicate the improved ability of the coating with a “frame-like” structure to deform in a “favorable” elastic region, as well as to resist mechanical contact loads even after the beginning of the plastic fl ow, grow to maximum values. For citation: Soboleva N.N., Makarov A.V., Stepchenkov A.K., Malygina I.Yu., Korobov Yu.S. In fl uence of thermal effects on the micromechanical properties of the nickel-chromium coating obtained by gas powder laser cladding. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science , 2020, vol. 22, no. 2, pp. 104–117. DOI: 10.17212/1994-6309-2020-22.2-104-117. (In Russian). ______ * Corresponding author Soboleva Natalia N. , Ph.D. (Engineering), Scienti fi c associate Institute of Engineering Science Ural Branch, Russian Academy of Sciences, 34 Komsomolskaya str., 620049, Yekaterinburg, Russian Federation Tel.: 8 (343) 362-30-33, e-mail: natashasoboleva@list.ru