Structure and phase composition of complexly alloyed powdered niobium containing nickel alloys

1988 ◽  
Vol 27 (3) ◽  
pp. 255-259
Author(s):  
L. E. Popova ◽  
V. I. Shvarts ◽  
V. F. Kotov ◽  
R. V. Lapina ◽  
G. B. Zvereva ◽  
...  
Keyword(s):  
Phase Composition ◽  
Nickel Alloys

scholarly journals Phase composition of galvanic iron-nickel alloys obtained using pulsed current

2021 ◽  
Vol 22 (1) ◽  
pp. 141-145
Author(s):  
R.P. Ganich ◽  
V.O. Zabludovsky ◽  
V.V. Artemchuk ◽  
Y.V. Zelenko ◽  
R.V. Markul
Keyword(s):  
Phase Composition ◽  
Nickel Alloys ◽  
Pulse Current ◽  
Equilibrium Diagram ◽  
Component Composition ◽  
Pulse Action ◽  
Unipolar Pulse ◽  
Iron Nickel ◽  
The Moment ◽  
Iron Nickel Alloys

The paper presents the results of studying the phase composition of iron-nickel alloys obtained by unsteady electrolysis. It was found that the use of a unipolar pulse current leads to a significant increase in the crystallization overvoltage at the crystallization front at the moment of the pulse action, which affects the component composition of the coatings. The phase composition of the alloys formed at the cathode differs from that shown in the iron-nickel equilibrium diagram.

Sintering process, structure, and phase composition of metal-graphite materials based on nickel alloys

1971 ◽  
Vol 10 (10) ◽  
pp. 786-789
Author(s):  
V. I. Itin ◽  
Yu. I. Kozlov ◽  
L. I. Pugina ◽  
A. G. Yurchenko ◽  
K. V. Savitskii ◽  
...  
Keyword(s):  
Phase Composition ◽  
Nickel Alloys ◽  
Sintering Process ◽  
Process Structure

Increasing the heat resistance of cast nickel-based complex alloyed alloys due to the influence of the redistribution of alloying elements between the γ-solid solution and the strengthening intermetallic γ'-phase

2020 ◽  
pp. 67-79
Author(s):  
O.M. Gubanov ◽  
V.N. Gadalov ◽  
Yu.V. Skripkina ◽  
I.A. Makarova
Keyword(s):  
Phase Composition ◽  
Heat Resistance ◽  
Nickel Alloys ◽  
Diffusion Processes ◽  
Distribution Coefficients ◽  
Alloying Elements ◽  
Maximum Heat ◽  
Alloying System ◽  
Heat Resistant ◽  
Positive Effect

The analysis of alloying of the chemical and phase composition of domestic and foreign cast heat-resistant alloys with a nickel matrix is carried out; the tendency to increase the level of heat-resistant properties of cast nickel alloys due to more complex alloying is traced. Recently, expensive rhenium, ruthenium, hafnium, and dysprosium have increasingly been used as alloying elements. The positive effect of these elements on the thermal stability of the γ-matrix and the strengthening γ'-phase is established. The above elements inhibit diffusion processes, thereby increasing the creep resistance of alloys at high temperatures and loads. The evaluation of heatresistant nickel alloys obtained by directional crystallization is given. It is established that the most significant parameters of the phase composition of the studied alloys are the distribution coefficients of alloying elements between the γ' and γ-phases (Ki). The basic principles of balanced alloying, which are used to select the optimal chemical composition of heat-resistant nickel alloys, are formulated. To achieve the maximum heat resistance parameters in the selected heat-resistant nickel alloys alloying system, the calculated value γ/γ' defined by “misfit” was used, which is calculated by the formula: Δа = (аγ-аγ')/ аγ, where аγ and аγ' are the lattice periods of γ and γʹ-phases. Thus, the calculated Δа should be positive for аγ> аγ' and at least two to three times more than for single-crystal heat-resistant nickel alloys with a traditional alloying system, for which Δа = (0.1-0.2) or more. It is shown that misfit (γ/γ') is mainly determined by those alloying elements that increase the аγ most significantly. These elements are Re, Pu, Mo, W, Nb, and Ta in ascending order of influence on the lattice period (аγ) of the phase.

Effect of Cerium and Lanthanum Additives on the Phase Composition of the Copper-Nickel Alloys

2019 ◽  
Vol 946 ◽  
pp. 123-128
Author(s):  
O.V. Samoilova ◽  
Evgeny A. Trofimov ◽  
E.R. Vakhitova
Keyword(s):  
Phase Composition ◽  
Cross Sections ◽  
Nickel Alloys ◽  
Microprobe Analysis ◽  
Nickel Concentration ◽  
Micro Hardness ◽  
X Ray ◽  
Different Content ◽  
Vickers Micro Hardness ◽  
Scanning Electron

An experimental study of the phase composition for nine samples of the Cu–Ni–Ce–La alloys with different content of components was carried out. The nickel concentration in the experimental samples varies from 3 to 40 wt. %, the sum of cerium and lanthanum concentrations was not exceed 7 wt. %. Alloys samples of the system Cu–Ni–Ce–La were studied using scanning electron microscopy and microprobe analysis, as well as X-ray analysis. Also, Vickers micro hardness was measured on the cross sections of the experimental samples. In this work, the conditions of intermetallic compounds formation in the as-cast samples were studied. The results of the work can be used for the technological processes analysis of copper and copper-based alloys production.

Phase composition of the diffusion layers of metallic coatings on heat-resistant nickel alloys

1994 ◽  
Vol 36 (12) ◽  
pp. 638-642
Author(s):  
E. N. Kablov ◽  
G. I. Morozova ◽  
G. N. Matveeva ◽  
S. A. Budinovskii
Keyword(s):  
Phase Composition ◽  
Nickel Alloys ◽  
Metallic Coatings ◽  
Heat Resistant ◽  
Diffusion Layers

scholarly journals The Importance of Phase Composition for Corrosion Resistance of Borided Layers Produced on Nickel Alloys

Materials ◽  
2020 ◽  
Vol 13 (22) ◽  
pp. 5131
Author(s):  
Natalia Makuch
Keyword(s):  
Corrosion Resistance ◽  
Phase Composition ◽  
Nickel Alloys ◽  
Chromium Content ◽  
Pure Nickel ◽  
High Susceptibility ◽  
Nickel Chromium ◽  
Chromium Alloys ◽  
Plasma Paste Boriding ◽  
Boriding Process

The plasma paste boriding process was used for production of the borided layers on pure nickel and nickel-chromium alloys. The produced layers consisted of nickel borides only (in the case of nickel) or a nickel and chromium borides mixture (in the case Ni–Cr alloys). The objective of this investigation was to indicate the importance of the presence of chromium for corrosion resistance of non-borided alloys, as well as to indicate the influence of phase composition of borided layers on their corrosion resistance. Pure nickel was characterized by higher corrosion resistance, in comparison to the nickel-based alloys. Increased chromium content in nickel alloys resulted in their high susceptibility for pitting corrosion. All borided samples were characterized by higher corrosion resistance than the non-borided samples. However, the phase composition of borided layers influenced their corrosion resistance. Due to the microstructure which consisted of one type of borides (nickel borides), borided nickel had the highest resistance to corrosion, whereas the presence of chromium borides in layers produced on nickel-chromium alloys caused a decrease in corrosion resistance.

Nickel Alloys in Directionally Solidified State – Characterisation of Microstructure and Phase Composition of the Alloys

2014 ◽  
Vol 782 ◽  
pp. 441-444
Author(s):  
Jitka Malcharcziková ◽  
Miroslav Kursa ◽  
Martin Pohludka
Keyword(s):  
Phase Composition ◽  
Directional Solidification ◽  
Nickel Alloys ◽  
Alloying Elements ◽  
Matrix Composition ◽  
Nominal Composition ◽  
Directionally Solidified ◽  
Variable Content ◽  
Microstructural Characterisation ◽  
Significant Chemical

The paper deals with the characterisation of the structure and phase composition of selected types of nickel alloys. Experimental alloys were prepared by vacuum induction casting. Castings were directionally solidified in corundum tubes with specified apex angle in the two-zone crystallisation furnace. Rate of directional solidification was 100 mm/h. Observation was carried out on the samples in the as-cast and directed state. Influencing of the structure by the process of directional solidification is evident. Porosity and micro-hardness were determined in transverse and longitudinal sections of individual samples and character of the formed structures was evaluated. Microstructural characterisation of materials was performed with use of scanning electron microscope. Distribution of individual elements was captured on X-ray maps, which documented significant chemical heterogeneity of investigated samples. Matrix composition corresponds approximately to the nominal composition of the alloys. The alloys contain moreover with variable content of primary and alloying elements. In the alloys with molybdenum and zirconium the phase enriched by these alloying elements were detected. On the other hand chromium is evenly dispersed in the basic matrix and it does not accumulate in the phases.

Sign in / Sign up

Export Citation Format

Share Document