Metastable States and Structural Phase Changes in Metals and Alloys Exposed to High Power Pulsed Ion Beams

1990 ◽  
pp. 17-52
Author(s):  
A. D. Pogbebnyak
Author(s):  
M. V. Zhidkov ◽  
A. E. Ligachev ◽  
Yu. R. Kolobov ◽  
G. V. Potemkin ◽  
G. E. Remnev

The study covers the topography and structural phase state of VT1-0 and VT6 submicrocrystalline titanium alloy subsurface layers irradiated by high power pulsed carbon ion beams (ion energy is 250 keV, pulse duration is ~100 ns, pulse current density is 150–200 A/cm2; surface energy density of a single pulse is j ~ 3 J/cm2 when irradiating VT1-0 titanium alloy samples and j ~ 1 J/cm2 when processing VT6 titanium alloy samples; pulse number is 1, 5, 10, and 50). The surface of samples was subjected to preliminary mechanical grinding and polishing before irradiation. It was shown that surface defects are formed on the surface of the alloys after irradiation, namely craters of different shapes and geometries with a diameter from fractions of a micron to 80–100 μm. At the same time, the grain structure in the subsurface layer becomes more homogeneous in terms of grain size and equiaxial properties. The initial state of titanium alloys is characterized by a fairly homogeneous structure with an average grain size of ~0,31 μm for VT1-0 and ~0,9 μm for VT6. After one irradiation pulse, grain growth to 0,54 μm in the transverse direction is observed in the subsurface layer of the VT1-0 alloy (j ~ 3 J/cm2), while grain size decreases to ~ 0,54 μm in the VT6 alloy (j ~ 1 J/cm2). After 50 pulses, the average grain size in the subsurface layer reaches ~2,2 μm for the VT1-0 alloy and ~1,6 μm for VT6. It should be noted that a rather uniform structure with equiaxed grains is formed as early as after treating with 1 high power ion beam pulse.


2009 ◽  
Vol 203 (17-18) ◽  
pp. 2608-2611 ◽  
Author(s):  
A.I. Ryabchikov ◽  
A.V. Petrov ◽  
V.K. Struts ◽  
A.V. Mytnikov ◽  
Yu.P. Usov ◽  
...  

2012 ◽  
Vol 3 (3) ◽  
pp. 220-225
Author(s):  
V. K. Struts ◽  
V. M. Matvienko ◽  
A. V. Petrov ◽  
A. I. Ryabchikov
Keyword(s):  

2020 ◽  
Vol 96 (4) ◽  
pp. 39-46
Author(s):  
S.A. Vodennikov ◽  
◽  
V.O. Skachkov ◽  
O.S. Vodennikova ◽  
◽  
...  

A conceptually new technology for the application of aluminum coatings on 18G2C steel by the electrolytically deposited NaF-NaCl - AlF3 ionic melt method has been developed. To solve the tasks set in the work, a set of experimental and computational research methods was used: metallographic analysis, energy dispersion microanalysis, mechanical tests, and calculation of the oxidation rate of samples. The mechanical characteristics of the samples of reinforcing steel were determined on a rupture machine FP-100 at an active capture rate of 2.5 mm / min. The relationship between the rates of electrochemical oxidation of the aluminide coating, its mechanical properties, with the distribution of aluminum in the depth of the samples and its phase composition have been determined. The increase of mechanical characteristics of samples from 18G2S steel with an aluminum covering in comparison with usual reinforcing steel is shown. The sequence of structural-phase changes of metal in the process of aluminide coating is determined and its influence on mechanical and corrosion resistance is determined. Experimental evaluation of the rate of oxidation of 18G2C steel samples with aluminum coating under the conditions of sulfuric acid electrolyte at an electric current of 11 to 18 A has been conducted. The developed technology of electrolytic deposition of aluminum has scientific and practical interest for the construction industry. The developed coating makes it possible to increase the mechanical properties of steel by almost 12% and to increase the corrosion resistance. Keywords: aluminum coatings, 18G2C steel, electrochemical oxidation, electrolytic deposition.


2020 ◽  
Vol 17 (34) ◽  
pp. 459-468
Author(s):  
Oksana A BYTSENKO ◽  
Igor G STESHENKO ◽  
Vladimir A PANOV ◽  
Victor V TISHKOV ◽  
Alexey B MARKOV

The development of aerospace engineering and mechanical engineering directly depends on the development of new metal materials and advanced technologies. The problem of creating materials and their types of processing to increase the level of operational properties is relevant in connection with the complication and tightening of working conditions of modern technologies. One of the most important tasks of contemporary aircraft construction is to increase the operational properties of the surface layer. The purpose of the article is to elucidate the effect of high-current electron beams of microsecond duration on changes in the surface layers of the heat-resistant multicomponent ion-plasma coating Ni-Cr-Al-Y under various conditions. Using a complex of metallophysical research methods, the physicochemical and structural-phase states of the surface layer were studied before and after modification of the samples. These samples were coated with heat-resistant condensed ion-plasma coatings of three different compositions using nine high-current electron beams in 9 modes with different values of electron energy and number of pulses in the selected interval of electron energy. An analysis of the structural phase changes occurring during modification was carried out. Cylindrical samples of targets made of heat-resistant nickel alloy ZhS36 coated with ion-plasma condensed multicomponent coating SDP-2 + VSDP-16. These samples were used according to serial technology, both with subsequent modification using highcurrent electron beams and without modification. It was found that chromium in the initial state is unevenly distributed: chromium is present in the particles; the matrix is depleted in chromium. The research results can be useful for scientists to study the properties of heat-resistant multicomponent ion-plasma coatings Ni-Cr-Al-Y and the effect of high-current electron beams on it, as well as for the manufacture of more heat-resistant materials in aerospace engineering and mechanical engineering.


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