scholarly journals Structure and corrosion in NaCl solution of quasicrystalline Al–Cu–Fe cast alloys and thin films

2019 ◽  
Vol 27 (1) ◽  
pp. 27-30 ◽  
Author(s):  
S. I. Ryabtsev ◽  
O. V. Sukhova ◽  
V. A. Polonskyy
Keyword(s):  
Cast Alloy ◽  
Film Surface ◽  
Nacl Solution ◽  
Sputtered Films ◽  
Plasma Sputtering ◽  
Ion Plasma ◽  
Cast Alloys ◽  
Fe Alloys ◽  
First Time ◽  
Potentiodynamic Method

For the first time, quasicrystalline Al60Cu28Fe12 films with 260 nm thickness cooled at 1012–1014 K/s were produced by the modernized method of three-electrode ion-plasma sputtering. Films were deposited on NaCl substrate. The structure of as-sputtered films was investigated in comparison with that of as-cast specimens by methods of quantitative metallography, X-ray analysis, and scanning electron microscopy. Corrosion behavior in 5% NaCl aqueous solution was studied by potentiodynamic method and model tests. In the structure of the as-cast Al–Cu–Fe alloy, the quasicrystalline icosahedral i-phase was established to co-exist with λ -Al13Fe4 , τ-AlCu(Fe), η-AlCu, and θ-Al2Cu crystalline phases and occupy ~56 % of the alloy volume. The Al–Cu–Fe film contains dispersive quasicrystalline i-phase (~3 nm in size) that is stable up to 723 К. Corrosion of the as-sputtered Al–Cu–Fe film runs at the lower rate as compared with that of the as-cast alloy of the same composition. Model corrosion tests for 1, 2, 3, 4, 8 days with 5% NaCl solution at 293 K indicate that the investigated Al–Cu–Fe film remains virtually untouched by corrosion. No marks of pittings typical for as-cast Al–Cu–Fe alloys are observed on the film surface affected by saline solution.

scholarly journals Получение пористого вольфрама из пленочных покрытий системы вольфрам-кадмий

2018 ◽  
Vol 44 (11) ◽  
pp. 63
Author(s):  
Ю.Ж. Тулеушев ◽  
В.Н. Володин ◽  
Е.А. Жаканбаев ◽  
Б.М. Сукуров ◽  
А.Л. Козловский
Keyword(s):  
Solid Solution ◽  
Crystalline Structure ◽  
Solid Solutions ◽  
Cadmium Concentration ◽  
The Other ◽  
Porous Tungsten ◽  
Plasma Sputtering ◽  
Ion Plasma ◽  
First Time

AbstractSolid solutions (alloys) with a Cd concentration of 50.3–76.3 at % were synthesized for the first time in the form of coatings by ion–plasma sputtering and codeposition of ultrafine W and Cd particles. When coatings were formed by tungsten and cadmium nanolayers, the components dissolved mutually to produce solid solutions of one metal in the other. A solid solution of cadmium in tungsten was synthesized at Cd concentrations up to 60.9 at %. At a cadmium concentration of 68.6 at % in the coating, the crystalline structure of cadmium with an admixture of amorphous tungsten was produced. At 800°C, tungsten evaporated from tungsten–cadmium coatings to form porous tungsten. The results of examination of materials fabricated on the basis of porous tungsten are planned to be used in practice.

scholarly journals The effect of Bi additives on the properties of Fe-Pt films

2019 ◽  
Vol 27 (2) ◽  
pp. 47-50
Author(s):  
V. F. Bashev ◽  
N. A. Kutseva ◽  
O. I. Kushnerov ◽  
S. I. Ryabtsev ◽  
O. V. Yelina ◽  
...  
Keyword(s):  
Coercive Force ◽  
X Ray Diffraction ◽  
Ceramic Substrates ◽  
Amorphous Phases ◽  
Sputtered Films ◽  
Plasma Sputtering ◽  
Ion Plasma ◽  
Metastable Structures ◽  
Nanocrystalline And Amorphous ◽  
Pt Films

Using the modernized three-electrode ion-plasma sputtering method, homogeneous thin films of FePt and Fe (Pt/Bi) were obtained. Films were deposited on NaCl and glass-ceramic substrates. The film thickness was 120-530 nm. In this case, the calculated cooling rate reached ~ 1012–1014 K/s. The structure of the FePt and Fe (Pt/Bi) films was investigated using X-ray diffraction and electron microscopy methods. It was established that metastable phases were formed in freshly sputtered films, including a supersaturated solid solution, a nanocrystalline and amorphous phases. It was determined that the obtained metastable structures are stable when heated to 540-880 K, depending on the composition. It was established that Bi additives significantly reduce the coercive force of films in the as-sputtered state. It was shown that a heat treatment increased the coercive force up to 36 kA/m in FePt films and up to 10 kA/m in Fe (Pt/Bi) films. The composition of Fe (Pt/Bi) films with a small value of the temperature coefficient of resistance (TCR ~3·10-5 K-1) was determined.

Characterization of Sputtered Films using the Scanning Electron Microscope

1973 ◽  
Vol 31 ◽  
pp. 44-45
Author(s):  
R. F. Schneidmiller ◽  
W. F. Thrower ◽  
C. Ang
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Thin Film Deposition ◽  
Film Deposition ◽  
Sputtered Films ◽  
Plasma Sputtering ◽  
Microelectronic Devices ◽  
Control Film ◽  
Scanning Electron

Solid state materials in the form of thin films have found increasing structural and electronic applications. Among the multitude of thin film deposition techniques, the radio frequency induced plasma sputtering has gained considerable utilization in recent years through advances in equipment design and process improvement, as well as the discovery of the versatility of the process to control film properties. In our laboratory we have used the scanning electron microscope extensively in the direct and indirect characterization of sputtered films for correlation with their physical and electrical properties.Scanning electron microscopy is a powerful tool for the examination of surfaces of solids and for the failure analysis of structural components and microelectronic devices.

Influence of Substituting La with Pr on Electrochemical Characteristics of RE–Mg–Ni-Based A2B7-Type Alloys Prepared by Melt Spinning

2012 ◽  
Vol 560-561 ◽  
pp. 1011-1015
Author(s):  
Yang Huan Zhang ◽  
Tai Yang ◽  
Hong Wei Shang ◽  
Ying Cai ◽  
Hui Ping Ren ◽  
...  
Keyword(s):  
Discharge Capacity ◽  
Melt Spinning ◽  
Hydrogen Diffusion ◽  
Cast Alloy ◽  
High Rate ◽  
Limiting Current ◽  
Electrochemical Characteristics ◽  
Electrochemical Hydrogen Storage ◽  
Cast Alloys ◽  
Rate Discharge

The RE–Mg–Ni-based A2B7-type La0.75−xPrxMg0.25Ni3.2 Co0.2Al0.1 (x = 0, 0.1, 0.2, 0.3, 0.4) electrode alloys were fabricated by casting and melt spinning. The microstructures and electrochemical characteristics of the as-cast and spun alloys were investigated in detail. The results indicate that the as-cast and spun alloys have a multiphase structure, consisting of two main phases (La, Mg)2Ni7 and LaNi5 as well as a residual phase LaNi2. The substitution of Pr for La results in a notable grain refinement of the as-cast alloys without altering the phase structure of the alloys. The discharge capacity of the alloys first rises and then falls with the variation of the Pr content. As Pr content grows from 0 to 0.4, the discharge capacity increases from 389.4 (x = 0) to 392.4 (x = 0.1) and then drops to 383.7 mAh/g (x = 0.4) for the as-cast alloy. And it mounts up from 393.5 (x = 0) to 397.9 (x = 0.1) and then declines to 382.5 mAh/g for the as spun (5 m/s) alloys. Furthermore, the measurements of the electrochemical hydrogen storage kinetics reveal that the high rate discharge ability (HRD), the limiting current density (IL) and the hydrogen diffusion coefficient (D) of the alloys first increases then decreases with the rising amount of Pr substitution.

INFLUENCE OF THE COMPOSITION OF THE RADIO-FREQUENCY SPUTTERING ATMOSPHERE ON THE DENSITY OF STATES AND INTERBAND LIGHT ABSORPTION IN THIN Y2O3 FILMS

2021 ◽  
Vol 88 (6) ◽  
pp. 881-886
Author(s):  
O. M. Bordun ◽  
I. O. Bordun ◽  
I. M. Kofliuk ◽  
I. Yo. Kukharskyy ◽  
I. I. Medvid
Keyword(s):  
Absorption Band ◽  
Density Of States ◽  
Interband Absorption ◽  
Long Wavelength ◽  
Plasma Sputtering ◽  
Radio Frequency Sputtering ◽  
Ion Plasma ◽  
Quasi Classical Approximation ◽  
Heavily Doped ◽  
Interband Light Absorption

The long-wavelength edge of the fundamental absorption band of thin Y2O3 films obtained by radiofrequency ion-plasma sputtering is investigated. The edge of interband absorption after annealing of the films in an atmosphere of argon, oxygen, or a mixture of these gases is shown to be approximated well by the Urbach empirical rule. Diffractograms of the obtained films were studied and a model of a heavily doped or defective semiconductor in the quasi-classical approximation was used to analyze the experimental results. This model allows determining the radius of the basic electronic state, the screening radius, and the rootmean-square potential depending on the sputtering atmosphere.

Structure and mechanical properties of cast quasicrystal-reinforced Mg–Zn–Al–Y base alloys

2004 ◽  
Vol 19 (5) ◽  
pp. 1531-1538 ◽  
Author(s):  
Guangyin Yuan ◽  
Kenji Amiya ◽  
Hidemi Kato ◽  
Akihisa Inoue
Keyword(s):  
Mechanical Properties ◽  
Elevated Temperatures ◽  
Cast Alloy ◽  
Strengthening Mechanism ◽  
Icosahedral Quasicrystal ◽  
Compression Tests ◽  
Strengthening Phase ◽  
Creep Tests ◽  
Cast Alloys ◽  
Bulk Alloys

The structure and mechanical properties of Mg–Zn–Al–Y base cast alloys containing an icosahedral quasicrystal phase (i-phase) as a main strengthening phase were investigated. Mg–8Zn–4Al–xY base bulk alloys containing the i-phase were prepared by casting into a copper mold at moderate cooling rates. The Y addition was effective for decreasing the size of the i-phase and the increasing the homogeneity of its dispersed state. The mechanical properties examined by compression tests at room temperature were much superior to those of a conventional AZ91 Mg alloy. The creep tests at elevated temperatures indicated a promising high temperature creep resistance of the quasicrystal-reinforced Mg–Zn–Al–Y cast alloy. The strengthening mechanism was also discussed.

scholarly journals Physical model of «substrate-coating» system structuring in complex modification processes of surface layers in working parts of dies and press molds

2018 ◽  
Vol 2018 (11) ◽  
pp. 35-41
Author(s):  
Олег Морозов ◽  
Oleg Morozov ◽  
Валерий Кокорин ◽  
Valeriy Kokorin ◽  
Владимир Табаков ◽  
...  
Keyword(s):  
Plastic Deformation ◽  
Physical Model ◽  
Cold Plastic Deformation ◽  
Coating System ◽  
Resistant Steel ◽  
Surface Layers ◽  
Heat Resistant Steel ◽  
Plasma Sputtering ◽  
Ion Plasma ◽  
Wear Coatings

Basic methods to increase durability of die working parts including processes of cold plastic deformation at anti-wear coatings application by a method of ion-plasma sputtering are considered. A physical model of cold plastic deformation of samples made of heat-resistant steel H12M is presented.

scholarly journals Применение покрытий AlN для защиты поверхности гетероструктур системы AlGaAs/GaAs от взаимодействия с атмосферным кислородом

2020 ◽  
Vol 46 (6) ◽  
pp. 16
Author(s):  
Е.В. Фомин ◽  
А.Д. Бондарев ◽  
И.П. Сошников ◽  
N.B. Bercu ◽  
L. Giraudet ◽  
...  
Keyword(s):  
Protective Coatings ◽  
Residual Pressure ◽  
Aluminum Oxynitride ◽  
Effective Protection ◽  
Pure Nitrogen ◽  
Plasma Sputtering ◽  
Laser Heterostructures ◽  
Ion Plasma ◽  
Thin Aluminum ◽  
Film Substrate

The paper presents the results of the synthesis of thin aluminum nitride films by reactive ion-plasma sputtering and the study of their properties with the aim of using as the protective coatings for the high-power AlxGa1-xAs/GaAs semiconductor laser heterostructures. EDS studies and ellipsometry showed that at a residual pressure in the chamber of the order of ~10-5 Torr, a layer of aluminum oxynitride is formed in the films. In this case, the film-substrate heterointerface can undergo oxidation. However, AlN films with a thickness of the order of 100 nm grown in a pure nitrogen medium with a residual pressure of ~10-7 Torr apparently do not contain oxygen, and can reliably prevent its penetration into the heterointerface region. Potentially, they can serve as effective protection for oxidation sensitive heterostructures.

scholarly journals Топография поверхности и оптические характеристики тонких пленок AlN на подложке GaAs (100), полученных методом реактивного ионно-плазменного распыления

2019 ◽  
Vol 45 (5) ◽  
pp. 38
Author(s):  
Е.В. Фомин ◽  
А.Д. Бондарев ◽  
A.I. Rumyantseva ◽  
T. Maurer ◽  
Н.А. Пихтин ◽  
...  
Keyword(s):  
Atomic Force Microscopy ◽  
Refractive Index ◽  
Surface Structure ◽  
Optical Characteristics ◽  
Process Conditions ◽  
Antireflection Coatings ◽  
Force Microscopy ◽  
Plasma Sputtering ◽  
Atomic Force ◽  
Ion Plasma

AbstractA study of the surface topography and optical characteristics of thin AlN films used as passivating and antireflection coatings deposited on n -GaAs (100) substrates by reactive ion-plasma sputtering is reported. It was found that the process conditions affect the structure and the optical characteristics of the films, which makes it possible to obtain coatings with prescribed parameters. An analysis of the results furnished by ellipsometry and atomic-force microscopy of the surface shows that the refractive index of the films is correlated with the surface structure.

scholarly journals HEAT AND EROSION-RESISTANT NANOSTRUCTURED COATINGS FOR GAS TURBINE ENGINES

Aviation ◽  
2013 ◽  
Vol 17 (4) ◽  
pp. 137-144 ◽  
Author(s):  
Aleksandrs Urbahs ◽  
Konstantins Savkovs ◽  
Margarita Urbaha ◽  
Kristine Carjova
Keyword(s):  
Gas Turbine ◽  
Oxidation Process ◽  
Sample Surface ◽  
Turbine Engines ◽  
Gas Turbine Engines ◽  
Functional Coatings ◽  
Temperature Oxidation ◽  
Plasma Sputtering ◽  
Ion Plasma ◽  
Basic Features

This work analyses the characteristics of functional coatings obtained by vacuum ion-plasma sputtering. These coatings have three-layer multiphase structure created as a result of condensing aluminium and titanium according to a certain programme. The article presents the results of investigation into the heat-resistance of ion-plasma coatings based on Ti-Al-N for titanium alloy parts of gas turbine engines. Analysis of the oxidation process between a sample surface and coatings within the range of 500–825 °C was carried out. The basic features of the process of coating destruction under high-temperature oxidation conditions were determined by means of scanning electron microscopy. The results of the tests made it possible to state that the coatings developed are able to operate at temperatures of 600–750 °C.

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