Search

Your search keyword '"Pochivalov, Yu. I."' showing total 36 results
Start Over Author "Pochivalov, Yu. I."
36 results on '"Pochivalov, Yu. I."'

20. The Effects of High-Energy Influence on the Structure and Fatigue Life of VT6 Titanium Alloy and Its Welded Joint.

Author

Smirnova, A. S., Pochivalov, Yu. I., Panin, V. E., Nasonovskaya, A. V., Malikov, A. G., and Orishich, A. M.

Subjects
*WELDED joints, *FATIGUE life, *TITANIUM alloys, *LASER welding, *SURFACE preparation, *CRYSTAL lattices
Abstract

In this study, a new surface treatment method was applied to laser welded joints of a high-strength VT6 titanium alloy. After welding, the welded joints were exposed to high energy electric pulse treatment in combination with ultrasonic forging. Ultrasonic forging creates a high-defect structure with high curvature of the crystal lattice in the surface layer, as evidenced by the appearance of extinction contours. The total number of cycles to failure is 8,700 for the samples untreated after welding and 29,400 for the treated samples, which indicates a significant increase in the fatigue life of the welded joint. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

21. Effect of Ultrasonic Impact Treatment on Mechanical Properties of 3D-Printed Ti-6Al-4V Titanium Alloy Parts.

Author

Panin, S. V., Pochivalov, Yu. I., Perevalova, O. B., Sinyakova, E. A., Kazachenok, M. S., Evtushenko, O. V., Buslovich, D. G., and Buyluk, A. O.

Subjects
*ULTRASONIC effects, *IMPACT (Mechanics), *TITANIUM alloys, *PRINT materials, *MICROSTRUCTURE, *MICROSCOPY
Abstract

Changes of the microstructure and phase composition of selective laser melting Ti-6Al-4V titanium alloy samples during ultrasonic impact post-processing were investigated by optical, transmission microscopy, and X-ray analysis. Significant refinement of the microstructure in the thin surface layer was observed as a result of ultrasonic impact treatment. This causes an increase in microhardness and strength characteristics of the surface layer of selective laser melting samples under uniaxial tension. [ABSTRACT FROM AUTHOR]

Published
2019
Full Text
View/download PDF

26. The Structure and Mechanical Properties of Welded Joints of 17Mn1Si Steel Subjected to Pulsed Mechanical-Electrophysical Treatment.

Author

Panin, S. V., Vlasov, I. V., Stankevich, R. V., Smirnova, A. S., Yakovlev, A. V., Pochivalov, Yu. I., and Valuev, D. V.

Subjects
WELDED joints, MECHANICAL behavior of materials, STRUCTURAL analysis (Engineering), STEEL, DEFORMATIONS (Mechanics)
Abstract

The structure and mechanical properties of specimens of welded joints of the 17Mn1Si pipe steel after modification by means of surface ultrasonic impact and combined pulsed mechano-electrophysical treatments is studied. The research was carried out on specimens cut from steel plates having an integral joint both in the heat-affected zone and directly in the weld. It is shown that the proposed treatment methods provide hardening of the surface layer, as well as an increase in tensile strength under static tension. The toughness of the specimens a) without welding (as supplied state), b) with a weld, and c) after modification of the surface layer was tested at room temperature and negative one, T = −70 °C. The differences revealed in the structure and deformation behavior of the specimens subjected to different treatment methods are shown and discussed. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

27. Features of Structure Change in the Contact Layer of Non-Ferrous Metals under the Influence of Electric Current at Dry Sliding against Steel 1045.

Author

Fadin, V. V., Aleutdinova, M. I., and Pochivalov, Yu. I.

Subjects
NICKEL-titanium alloys, ELECTRIC currents, IRON compounds, SLIDING friction, ELECTRIC conductivity
Abstract

Dry sliding of copper, nickel, titanium and a nitinol alloy (NiTi) against a steel counterbody is carried out under the influence of high-density electric current. It is shown that the surface layer of these metals undergoes phase transformation and forms a tribolayer. It is noted that the high strength of the tribolayer corresponds to high contact electrical conductivity and to low wear intensity. The tribolayer of a nitinol alloy has a weak connection with the basic material. This factor, as well as low thermal conductivity and the presence of a superstructure of the nitinol alloy, leads to its rapid deterioration. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

31. Modification of the Structure of Low-Carbon Pipe Steel by Helical Rolling, and the Increase in Its Strength and Cold Resistance.

Author

Derevyagin, L. S., Gordienko, A. I., Pochivalov, Yu. I., and Smirnova, A. S.

Abstract

The paper reports the investigation results on the microstructure and mechanical properties of low-carbon pipe steel after helical rolling. The processing of the steel leads to the refinement of ferritic grains from 12 (for the coarse-grained state) to 5 µm, to the strengthening of ferrite by carbide particles, a decrease in the total fraction of perlite grains, a more uniform alternation of ferrite and perlite, and the formation of regions with bainitic structure. The mechanical properties of the steel have been determined in the conditions of static and dynamic loading in the range of test temperatures from +20 to -70°C. As a result of processing, the ultimate tensile strength increases (from 650 to 770 MPa at a rolling temperature from 920°C) and the viscoplastic properties at negative temperatures are improved significantly. The ductile-brittle transition temperature of the rolled steel decreases from -32 to -55°C and the impact toughness at the test temperature-40°C increases eight times compared to the initial state of the steel. [ABSTRACT FROM AUTHOR]

Published
2018
Full Text
View/download PDF

32. Consolidation and mechanical properties of metal and intermetallic matrix nanocomposites produced using high-energy ball milling

Author

Panin V., E., Korchagin M., A., Lomovsky O., I., Dudina D., V., Panin S., V., Durakov V., G., Pochivalov Yu, I., and Stepanova I., V.

Abstract

Synthesis of nanocomposites in TiB2-Cu, TiB2-Cu-Ni, TiB2-NiTi systems was developed using a combination of high-energy ball milling and self-propagating high-temperature synthesis (SHS). Consolidation behavior of nanocomposite powders, microstructures and mechanical properties of the bulk were investigated in view of developing new materials with high temperature stability and increased strength. This work was financially supported by SB RAS integration project No. 93. "Design of Principles and Technologies of Nanostructured State Formation in Surface Layers and Internal Interfaces of Reliable Structural and Functional Materials".

Published
2004
Full Text
View/download PDF

34. Sequence of structural-phase states during implantation of C+, N+, and Si+ ions into molybdenum

Author

Korotaev, A. D., Bekhert, A. É., Tyumentsev, A. N., Bugaev, S. P., and Pochivalov, Yu. I.

Abstract

The sequence of structural-phase changes in the surface layer of molybdenum during pulsed implantation of N+, C+, and Si+ ions has been studied. At radiation doses ?5·1016 cm-2 we detected qualitatively similar structural-phase transformations with the formation of highly dispersed secondary-phase particles (nitrides, carbides, and silicides), dislocations, point defects, and clusters of defects. At radiation doses (1–2)·1017 cm-2 implantation of C+ and Si+ ions causes amorphization of the surface layer; nitrogen implantation is accompanied by the formation of continuous layers of the nitride phase on the surface.

Published
1994
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results