scholarly journals Liquid-phase boriding of high-chromium steel

2020 ◽  
Vol 63 (7) ◽  
pp. 539-547
Author(s):  
Yu. F. Ivanov ◽  
V. E. Gromov ◽  
D. A. Romanov ◽  
O. V Ivanova ◽  
A. D. Teresov
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Materials Science ◽  
Titanium Boride ◽  
Relative Mass ◽  
Initial State ◽  
Boron Powder ◽  
Pulsed Electron Beam ◽  
Titanium Borides ◽  
Electroexplosive Alloying

Using the methods of modern physical materials science, structuralphase states and tribological properties of 12Kh18N10T steel, subjected to electroexplosive alloying with titanium and boron and subsequent electron-beam processing in various modes depending on electron beam energy density, exposure pulse duration and their quantity have been analyzed. It has been established that electroexplosive alloying of steel with titanium and boron leads to formation of surface layer with multiphase submicro-nanocrystalline structure, characterized by presence of micropores, microcracks, and microcraters. Complex processing, combining electroexplosive alloying and subsequent irradiation with high-intensity pulsed electron beam, leads to formation of 60 μm thick multiphase submicro-nanocrystalline surface layer. It is shown that phase composition of surface layer of steel is determined by mass ratio of titanium and boron during electroexplosive alloying. Microhardness of modified layer is defined by relative mass fraction of titanium borides in surface layer and can be more than 18 times higher than microhardness of steel in its initial state (before electroexplosive alloying). Modes of complex processing have been determined at which surface layer containing exclusively titanium borides and intermetallic compounds based on titanium and iron is formed. The maximum (approximately 82 % by weight) titanium boride content is observed when steel is processed at regime with the highest mass of boron powder in the sample (mB = 87.5 mg; mTi /mB = 5.202). With decrease in mass of boron powder, relative content of borides in surface layer of steel decreases. It was found that integrated processing of steel is accompanied by sevenfold increase in microhardness of surface layer, wear resistance of steel increases by more than nine times.

scholarly journals Effect of Structural and Phase Changes under Relativistic Electron Pulsed Beam Irradiation on the Aluminum Alloys Micro-hardness

2021 ◽  
Vol 22 (4) ◽  
pp. 655-663
Author(s):  
V.V. Bryukhovetsky ◽  
V.V. Lytvynenko ◽  
D.E. Myla ◽  
V.A. Bychko ◽  
Yu.F. Lonin ◽  
...  
Keyword(s):  
Surface Layer ◽  
Aluminum Alloy ◽  
Electron Beam ◽  
Relativistic Electron ◽  
Relativistic Electron Beam ◽  
Phase Changes ◽  
Micro Hardness ◽  
Initial State ◽  
Pulsed Electron Beam ◽  
Value Changes

The paper studies the distinctive features of micro-hardness value changes in the zone of industrial aluminum alloy 1933 and alloy 1380 irradiated by the relativistic electron beam. The surface layer was modified under the relativistic electron beam injected along with the equal energy parameters. However, we have to claim that some physical and technological properties of the irradiated alloys layer came with some differences. The modified layer micro-hardness increased over 30% in 1933 aluminum alloy and decreased by 10% in 1380 aluminum alloy. The mechanisms affecting the metal material strengthening transformation after a pulsed electron beam application are analyzed. Thus it was established that one of the core impacts to increase the micro-hardness of 1933 aluminum alloy surface layer was fine MgO impurities being absent in the initial alloy and caused by the irradiation, whilst the micro-hardness of the irradiated layer of the 1380 aluminum alloy decreases due to the dissolution during irradiation of the strengthening phases, which were identified in the initial state.

A Study of Electrically Active Defects Induced by Pulsed Electron Beam Annealing In (100) N-Type Virgin Silicon

1984 ◽  
Vol 35 ◽  
Author(s):  
M.S. Doghmane ◽  
D. Barbier ◽  
A. Laugier
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Layer Thickness ◽  
Schottky Contacts ◽  
Probable Mechanism ◽  
Electron Trap ◽  
Melting Layer ◽  
Pulsed Electron Beam ◽  
Depth Profiles ◽  
Electron Beam Pulse

ABSTRACTAu/Si Schottky contacts have been used as test structures to investigate defects induced in virgin C.Z (100) N-type silicon after irradiation with a 12 to 20 KeV mean energy electron beam pulse. A thin and highly damaged surface layer was observed from a fluence threshold of 1 J/cm2. In addition electron traps were detected in the PEBA induced melting layer with concentrations in the 1012-1013 cm-3 range. Their depth profiles have been related to the PEBA induced melting layer thickness. Quenching of multidefect complexes is the most probable mechanism for electron trap generation in the processed layer.

The structure and phase condition's evolution in the silicon carbide ceramics surface layer under the electron-beam treatment

2018 ◽  
pp. 24-28
Author(s):  
Yu. F. Ivanov ◽  
O. L. Khasanov ◽  
M. S. Petyukevich ◽  
V. V. Polisadova ◽  
Z. G. Bikbaeva ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Surface Layer ◽  
Electron Beam ◽  
Electron Beam Treatment ◽  
Pulsed Electron Beam ◽  
Sic Ceramics ◽  
Treatment Conditions ◽  
Carbide Ceramics ◽  
Silicon Carbide Ceramics ◽  
Beam Characteristics

The elemental constituents, phase composition and substructural evolution were investigated in the article in the silicon carbide ceramics surface layer which was subjected to the intense pulsed electron beam the density of the electron beam being varied. It was shown that the ceramic layer surface's structure and phase conditions were controlled by the electron beam characteristics. The SiC-ceramics surface layer nanostructuring was detected and the electron beam treatment conditions which lead to this effect were defined.

Microstructure Analysis of HPb59-1 Brass Induced by High Current Pulsed Electron Beam

2016 ◽  
Vol 35 (7) ◽  
pp. 715-721
Author(s):  
Jike Lyu ◽  
Bo Gao ◽  
Liang Hu ◽  
Shuaidan Lu ◽  
Ganfeng Tu
Keyword(s):  
Residual Stress ◽  
Surface Layer ◽  
Electron Beam ◽  
Surface Properties ◽  
Microstructure Evolution ◽  
High Current ◽  
Pulsed Electron Beam ◽  
Β Phase ◽  
Nanocrystalline Structures ◽  
Two Phases

AbstractIn this paper, the effects of high current pulsed electron beam (HCPEB) on the microstructure evolution of casting HPb59-1 (Cu 57.1 mass%, Pb 1.7 mass% and Zn balance) alloy were investigated. The results showed a “wavy” surface which was formed with Pb element existing in the forms of stacking block and microparticles on the top surface layer after treatment. Nanocrystalline structures including Pb grains and two phases (α and β) were formed on the top remelted layer and their sizes were all less than 100 nm. The disordered β phase was generated in the surface layer after HCPEB treatment, which is beneficial for the improvement of surface properties. Meanwhile, there was a large residual stress on the alloy surface, along with the appearance of microcracks, and the preferred orientations of grains also changed.

Surface Treatment of Materials with High Current Pulsed Electron Beam

2005 ◽  
Vol 475-479 ◽  
pp. 3959-3962 ◽  
Author(s):  
Sheng Zhi Hao ◽  
B. Gao ◽  
Ai Min Wu ◽  
Jian Xin Zou ◽  
Ying Qin ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Surface Layer ◽  
Electron Beam ◽  
Surface Treatment ◽  
Short Pulse ◽  
Research Work ◽  
High Current ◽  
Near Surface ◽  
Pulsed Electron Beam ◽  
Dynamic Stress Field

High current pulsed electron beam (HCPEB) is now becoming a promising energetic source for the surface treatment of materials. When the concentrated electron flux transferring its energy into a very thin surface layer within a short pulse time, superfast processes such as heating, melting, evaporation and consequent solidification, as well as dynamic stress field induced by an abrupt thermal distribution in the interactive zone impart surface layer with improved physicochemical and mechanical properties. The present paper reports mainly our experimental research work on this new-style technique. Investigations performed with a variety of constructional materials (aluminum, carbon and mold steel, magnesium alloys) have shown that the most pronounced changes of composition, microstructure and properties occur in the near-surface layers, while the thickness of the modified layer with improved mechanical properties (several hundreds of micrometers) is significantly greater than that of the heat-affected zone due to the propagation of stress wave. The surfaces treated with either simply several pulses of bombardment or complex techniques, such as rapid alloying by HCPEB can exhibit improved mechanical and physicochemical properties to some extent.

scholarly journals Multi-cycle of AISI 5135 steel modification by irradiation of the “film (Si (0.2 μm) + Nb (0.2 μm))/(AISI 5135 steel) substrate” system with an intense pulsed electron beam

2021 ◽  
Vol 2064 (1) ◽  
pp. 012041
Author(s):  
N N Koval ◽  
Yu F Ivanov ◽  
V V Shugurov ◽  
A D Teresov ◽  
E A Petrikova
Keyword(s):  
Wear Resistance ◽  
Surface Layer ◽  
Electron Beam ◽  
High Speed ◽  
Steel Substrate ◽  
High Hardness ◽  
High Strength ◽  
Pulsed Electron Beam ◽  
Impact Area ◽  
Steel Aisi

Abstract Steel AISI 5135 surface layer modification carried out by high-cycle high-speed melting of the “film (Si + Nb)/(steel AISI 5135) substrate” system with an intense pulsed electron beam with an impact area of several square centimeters, have been implemented in a single vacuum cycle on the “COMPLEX” setup. The regime of the system “film (Si (0.2 μm) + Nb (0.2 μm))/(steel AISI 5135) substrate” irradiation with an intense pulsed electron beam (20 J/cm2, 200 μs, 3 pulses, 3 cycles) which makes it possible to form a surface layer with high thermal stability have been revealed. This layer is characterized by high hardness, more than 3 times higher than the hardness of AISI 5135 steel in the original (ferrite-pearlite structure) and wear resistance, more than 90 times higher than the wear resistance of the initial AISI 5135 steel. It is shown that the high strength and tribological properties of steel are due to the formation of the hardening phase particles (niobium silicide of Nb5Si3 composition).

scholarly journals Structure and properties of high-chromium steel irradiated with a pulsed electron beam and nitrided in a low-pressure gas discharge plasma

2021 ◽  
Vol 2064 (1) ◽  
pp. 012043
Author(s):  
Y Ivanov ◽  
E Petrikova ◽  
A Teresov ◽  
S Lykov ◽  
O Tolkachev ◽  
...  
Keyword(s):  
Wear Resistance ◽  
Surface Layer ◽  
Electron Beam ◽  
Low Pressure ◽  
Developed Countries ◽  
Gas Discharge ◽  
Iron Nitride ◽  
Complex Method ◽  
Two Phase ◽  
Pulsed Electron Beam

Abstract Ion-plasma saturation of the surface of machine parts and mechanisms with gas elements (nitrogen, oxygen, carbon) is currently one of the most effective and widely used methods of surface hardening of metal products for various purposes in the industry of developed countries. The aim of this research is to develop a complex method for modifying the surface layer of AISI 310 steel, combining irradiation with an intense pulsed electron beam and subsequent nitriding in the plasma of a low-pressure gas discharge. As a result of the studies performed, the optimal parameters of modification were revealed, which make it possible to increase the hardness of the surface layer of steel by more than 11 times, relative to the hardness of the initial material, and 8 times, relative to the hardness of steel irradiated with a pulsed electron beam. In this case, the wear resistance of the steel exceeds the wear resistance of the original and irradiated material by more than 100 times. It has been established that the high strength and tribological properties of the modified steel are due to the formation of a two-phase (iron nitride and chromium nitride) layered nanoscale structure in the surface layer.

scholarly journals REDISTRIBUTION OF CARBON ATOMS IN DIFFERENTIALLY CHARGED RAILS FOR LONG-TERM OPERATION

2018 ◽  
Vol 61 (6) ◽  
pp. 454-459 ◽  
Author(s):  
V. E. Gromov ◽  
A. A. Yur’ev ◽  
Yu. F. Ivanov ◽  
V. A. Grishunin ◽  
S. V. Konovalov
Keyword(s):  
Surface Layer ◽  
Phase Composition ◽  
Materials Science ◽  
Rail Steel ◽  
Ferrite Matrix ◽  
Crystalline Lattice ◽  
Initial State ◽  
Term Operation ◽  
Prolonged Operation ◽  
Rolling Surface

Using  transmission  electron  microscopy  methods  at  various  distances from the rolling surface along the central axis, changes in  structure, phase composition, and defective substructure of the head  of differentially hardened rails were studied after passed tonnage of  691.8  million tons of gross weight. It is confirmed that prolonged  operation of rails is accompanied by two simultaneous processes of  transformation of structure and phase composition of plate-pearlite  colonies: cutting of cementite plates and dissolution of cementite  plates. The first process is carried out by mechanism of cutting carbide  particles and removing their fragments, accompanied only by change  in their linear dimensions and morphology. The second process of  dest ruction of the cementite plates of perlite colonies is carried out by  leaving carbon atoms from crystalline lattice of cementite on dislocation, as a result of which phase transformation of rails metal is possible. This is due to a noticeable relaxation of mean energy of carbon  atom  s binding to dislocations (0.6  eV) and to iron atoms in cementite  lattice (0.4  eV). The stages of transformation of cementite plates are considered: enveloping the plates with sliding dislocations and then  splitting them into weakly oriented fragments; penetration of sliding  dislocations from ferrite lattice into lattice of cementite; dissolution of  cementite and formation of nanoscale particles. The presence of nanosized cementite particles in ferrite matrix is noted due to their removal  during dislocation slide. Using expressions of modern physical materials science and X-ray diffraction analysis, influence of content of  carbon atoms on structural elements of rail steel was estimated. It is  shown that prolonged operation of rails is accompanied by a significant  redistribution of carbon atoms in surface layer. In the initial state, the  main quantity of carbon atoms is concentrated in cementite particles,  and after a long operation of rails, along with cementite particles, carbon is located in defects of crystal structure of steel (dislocation, grain  boundaries and subgrains), and in the surface layer of steel atoms carbon is also found in crystal lattice based on α-iron.

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