scholarly journals Formation Mechanism of Micro- and Nanocrystalline Surface Layers in Titanium and Aluminum Alloys in Electron Beam Irradiation

Metals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1399
Author(s):  
Sergei Nevskii ◽  
Vladimir Sarychev ◽  
Sergey Konovalov ◽  
Alexey Granovskii ◽  
Victor Gromov
Keyword(s):  
Mathematical Model ◽  
Electron Beam ◽  
Field Strength ◽  
Electron Beam Irradiation ◽  
Electron Beams ◽  
Hydrodynamic Instabilities ◽  
Beam Irradiation ◽  
Surface Layers ◽  
Reported Study ◽  
Capillary Evaporation

The reported study discusses the formation of micro- and nanocrystalline surface layers in alloys on the example of Ti-Y and Al-Si-Y systems irradiated by electron beams. The study has established a crystallization mechanism of molten layers in the micro-and nanodimensional range, which involves a variety of hydrodynamic instabilities developing on the plasma–melt interface. As suggested, micro- and nanostructures form due to the combination of thermocapillary, concentration and capillary, evaporation and capillary and thermoelectric instabilities. This mechanism has provided the foundation for a mathematical model to describe the development of structures in focus in the electron beam irradiation. The study has pointed out that thermoelectric field strength E ≥ 106 V/m is attributed to the occurring combination of instabilities in micro- and nanodimensional ranges. A full dispersion equation of perturbations on the melt surface was analyzed.

scholarly journals EFFECT OF HIGH-CURRENT ELECTRON BEAM IRRADIATION ON RESISTANCE OF SULFIDE-OXIDE CORROSION OF NI-CR-AL-Y ION-PLASMA COATINGS

2019 ◽  
Vol 16 (33) ◽  
pp. 198-205
Author(s):  
O. A. BYTSENKO ◽  
A. V. SHATILOV ◽  
A. I. DANEKO ◽  
E. V. FILONOVA ◽  
A. B. MARKOV
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Electron Beams ◽  
Sample Surface ◽  
High Current ◽  
Beam Irradiation ◽  
High Current Electron Beam ◽  
Ion Plasma ◽  
Current Electron ◽  
High Current Electron

Recently, the emergence of accelerators of high-current electron beams and powerful electron ion beams has contributed to the creation of unique effects of concentrated energy flows on materials. Upgrading of production processes and development of new technological processes of both domestic aircraft propulsion engineering and aviation arms remain topical and needed. Engine operational reliability depends on that of turbine blades. They are the most loaded details because they are experienced to action of static, dynamic and cyclic loadings as well as are subjected to cyclic thermal stresses. Therefore the main objective of our paper is to analyze the effect of high-current electron beam irradiation on-resistance of sulfide-oxide corrosion (SOC)of Ni-Cr-Al-Yion-plasma coatings. To achieve this purpose, beam irradiation was performed using the RITM-SP complex automated electron-beam setup. Modification of surface layer of SDP 2+VSDP16 ion-plasma coating by microsecond high-current electron beams of selected mode made it possible to increase considerably the SOC resistance. An analysis of the surface and microstructure of samples after SOC testing enabled to determine different effects of medium on sample coating depending on the state of the sample surface. When investigated samples microstructure, we found that after modification certain cracks on sample surface did not develop in the course of testing. It was found that some craters were not necessarily centers of corrosion damage origin, i.e., the existence of given types of craters and their impact on SOC resistance stability are ambiguous.

scholarly journals Formation of a Nanostructured Hardened Surface Layer on the TiC-(Ni-Cr) Metal-Ceramic Alloy by Pulsed Electron-Beam Irradiation

2020 ◽  
pp. 421-459
Author(s):  
Vladimir E. Ovcharenko ◽  
Konstantin V. Ivanov ◽  
Bao Hai Yu
Keyword(s):  
Surface Layer ◽  
Electron Beam ◽  
Phase Composition ◽  
Electron Beam Irradiation ◽  
Strength Properties ◽  
Beam Irradiation ◽  
Surface Layers ◽  
Pulsed Electron Beam ◽  
Metal Ceramic ◽  
Hardened Surface

AbstractThe efficiency and service life of products made from metal-ceramic tool alloys and used as cutting tools and friction units are determined by a combination of physical and strength properties of their surface layers with a thickness of up to 200 μm. Therefore, much attention is paid to their improvement at the present time. An effective way to increase the operational properties of the metal-ceramic alloy products is to modify the structure and the phase composition of the surface layers by forming multi-scale internal structures with a high proportion of low-dimensional (submicro and nano) components. For this purpose, surfaces are treated with concentrated energy fluxes. Pulse electron-beam irradiation (PEBI) in an inert gas plasma is one of the most effective methods. This chapter presents results of theoretical and experimental studies of this process. An example is the nanostructured hardened surface layer on the TiC-(Ni-Cr) metal-ceramic alloy (ratio of components 50:50) formed by PEBI in the plasma of argon, krypton, and xenon. Its multi-level structure, phase composition, as well as tribological and strength properties are shown.

Study thermodynamic assessment of the B-C and B-Si binary systems with swift heavy ions and high intense electron beam irradiation at the low temperature

2020 ◽  
Vol 34 (34) ◽  
pp. 2050395
Author(s):  
Matlab N. Mirzayev
Keyword(s):  
Electron Beam ◽  
Low Temperature ◽  
Heavy Ions ◽  
Electron Beam Irradiation ◽  
Electron Beams ◽  
High Energy ◽  
Beam Irradiation ◽  
Swift Heavy Ions ◽  
Intense Electron Beam ◽  
Intense Electron

B4C and B6Si samples have been irradiated by using swift heavy ions and high intense electron beam. Ion irradiation of the samples was carried at the different electron fluences [Formula: see text], [Formula: see text] and [Formula: see text] cm[Formula: see text] ion/cm2, and energy of ions flux 167 MeV. Also, the samples were irradiated with high energy electron beams at the linear electronic accelerator at different electron fluencies up to [Formula: see text] cm[Formula: see text] and energy of electron beams 2.5 MeV and current density of electron beams [Formula: see text]s. The unirradiation and irradiation of the thermodynamic kinetics of samples at low-temperature change with a differential mechanism. In the DSC curves, at the low temperature for unirradiation and irradiation, boron carbide and boron silicide samples do not undergo phase transition. But at the [Formula: see text] K temperature range, the thermodynamic mechanism of ions and electron beam irradiation are very difficult and measuring the temperature of conductivity, thermal conductivity, calibration factor, specific heat capacity becomes more complicated.

Methods to Monitor and Improve the Performance of Specimen Holders for Transmission Electron Cryomicroscopy

1996 ◽  
Vol 54 ◽  
pp. 454-455
Author(s):  
B. L. Armbruster ◽  
B. Kraus ◽  
M. Pan
Keyword(s):  
Electron Microscopy ◽  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Beam Irradiation ◽  
Quality Of Data ◽  
Electron Cryomicroscopy ◽  
Thermal Equilibration ◽  
Transmission Electron ◽  
Electron Microscopes

One goal in electron microscopy of biological specimens is to improve the quality of data to equal the resolution capabilities of modem transmission electron microscopes. Radiation damage and beam- induced movement caused by charging of the sample, low image contrast at high resolution, and sensitivity to external vibration and drift in side entry specimen holders limit the effective resolution one can achieve. Several methods have been developed to address these limitations: cryomethods are widely employed to preserve and stabilize specimens against some of the adverse effects of the vacuum and electron beam irradiation, spot-scan imaging reduces charging and associated beam-induced movement, and energy-filtered imaging removes the “fog” caused by inelastic scattering of electrons which is particularly pronounced in thick specimens.Although most cryoholders can easily achieve a 3.4Å resolution specification, information perpendicular to the goniometer axis may be degraded due to vibration. Absolute drift after mechanical and thermal equilibration as well as drift after movement of a holder may cause loss of resolution in any direction.

A Study of Electron Beam Irradiation Influence on Device Contact Junction Characteristics of Advanced DRAM Using Atomic Force Probing

2013 ◽  
Author(s):  
Wei-Chih Wang ◽  
Jian-Shing Luo
Keyword(s):  
Electron Beam ◽  
Electron Beam Irradiation ◽  
Forward Bias ◽  
Irradiation Damage ◽  
Beam Irradiation ◽  
Excess Current ◽  
Atomic Force ◽  
Order Of Magnitude ◽  
Voltage Contrast ◽  
Acceleration Voltage

Abstract In this paper, we revealed p+/n-well and n+/p-well junction characteristic changes caused by electron beam (EB) irradiation. Most importantly, we found a device contact side junction characteristic is relatively sensitive to EB irradiation than its whole device characteristic; an order of magnitude excess current appears at low forward bias region after 1kV EB acceleration voltage irradiation (Vacc). Furthermore, these changes were well interpreted by our Monte Carlo simulation results, the Shockley-Read Hall (SRH) model and the Generation-Recombination (G-R) center trap theory. In addition, four essential examining items were suggested and proposed for EB irradiation damage origins investigation and evaluation. Finally, by taking advantage of the excess current phenomenon, a scanning electron microscope (SEM) passive voltage contrast (PVC) fault localization application at n-FET region was also demonstrated.

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