The effect of hot plastic deformation on the structure and properties of surface-modified layers after non-vacuum electron beam surfacing of a powder mixture of composition 10Cr-30B on steel 0.12 C-18 Cr-9 Ni-Ti
Authors:   Novosibirsk State Technical University, Russian Federation, Dudareva Alina , Bushueva Evdokia ,   Novosibirsk State Technical University, Russian Federation, Tyurin Andrey ,   Novosibirsk State Technical University, Russian Federation, Domarov Evgeny ,   Budker Institute of Nuclear Physics of Siberian Branch Russian Academy of Sciences, Novosibirsk, Nasennik Igor ,   Novosibirsk State Technical University, Russian Federation,   “Federal Research Center “G.K. Boreskov Institute of Catalysis of the Siberian Branch of the Russian Academy of Sciences”, Center for Collective Use “Siberian Ring Photo Source”, Koltsovo, Novosibirsk region, Shikalov Vladislav ,   Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russian Federation, Skorokhod Ksenia ,   Khristianovich Institute of Theoretical and Applied Mechanics SB RAS, Novosibirsk, Russian Federation, Legkodymov Alexander ,   Budker Institute of Nuclear Physics of Siberian Branch Russian Academy of Sciences, Novosibirsk,   “Federal Research Center “G.K. Boreskov Institute of Catalysis of the Siberian Branch of the Russian Academy of Sciences”, Center for Collective Use “Siberian Ring Photo Source”, Koltsovo, Novosibirsk region
Published: December 2024

Introduction. Currently, austenitic Ni-Cr steels are widely used in the oil and gas industry for drilling wells due to its high corrosion resistance, non-magnetic properties, high impact strength, ductility and weldability. However, in order to increase the service life of products, it is necessary to increase the abrasive resistance of the surface layers while maintaining chemical resistance, which is a difficult technological task. The solution to such a problem can be the creation of sheet blanks “austenitic Ni-Cr steel - modified layer” subjected to hot plastic deformation. The purpose of the work is to study the effect of hot plastic deformation on the structure and phase composition of “modified layer – base metal” compositions obtained by the method of non-vacuum electron beam surfacing of a powder mixture of boron and chromium on austenitic Ni-Cr steel 0.12 C-18 Cr-9 Ni-Ti. Material and methods of research. The work investigated specimens made of steel 0.12 C-18 Cr-9 Ni-Ti with a modified 10Cr-30B layer formed by non-vacuum electron beam surfacing of a powder mixture of chromium and boron, and subsequent hot plastic deformation at a temperature of 950 °C. The research methods are mechanical tests for microhardness, X-ray spectral analysis of the modified layer, metallographic studies, profile analysis, calculation of lattice parameters. Results and discussion. It is revealed that after deformation, defect-free compositions are obtained, the surface layer of which is a matrix composite material containing oriented chromium carbide particles with altered crystal lattice parameters. After plastic deformation, cracks and delamination are not recorded, which allows us to speak about the high quality of the “modified layer – base metal” compositions with increased hardness values exceeding 6.5 times as-delivered steel 0.12 C-18 Cr-9 Ni-Ti (3…11 GPa and 2 GPa, respectively). In the modified layer, complex borides of type (FexCry)B are formed and located in a γ-solid solution of iron. The lattice parameter decreases for γ-iron from 3.588 Å to 3.580 Å, for boride parameter a from 5.126 Å to 5.111 Å, parameter c from 4.228 Å to 4.199 Å.