Mathematical forecasting composition of secondary carbides in the single-crystal superalloys

Purpose: Predicting the specifics of the distribution of alloying elements between secondary carbides, their topology, and morphology, as well as the composition for a single-crystal multicomponent system of the type Ni-11.5Cr-5Co-3.6Al-4.5Ti-7W-0.8Mo-0.06C using the calculated CALPHAD (passive experiment) versus scanning electron microscopy (active experiment). Design/methodology/approach: This work presents the results of studies of the distribution of chemical elements in the composition of carbides, depending on their content in the system. The studies were carried out using an electron microscope with computer analysis of images and chemical composition. Findings: It was found that the influence of alloying elements on the composition of carbides is complex and is described by complex dependencies that correlate well with the obtained experimental results. Research limitations/implications: An essential problem is the prediction of the structure and properties of superalloys without or with a minimum number of experiments. Practical implications: The obtained dependencies can be used both for designing new superalloys and for improving the compositions of industrial alloys. Originality/value: The value of this work is that the obtained dependences of the influence of alloying elements on the dissolution (precipitation) temperatures and the distribution of elements in secondary carbides in the superalloy of the Ni-11.5Cr-5Co-3.6Al-4.5Ti-7W-0.8Mo-0.06C system. It was found that changes in the course of the curves of temperature dependence on the element content closely correlate with thermodynamic processes occurring in the system, that is, the curves exhibit extrema accompanying the change in the stoichiometry of carbides or the precipitation of new phases.

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Modelling the composition of carbides in nickel-based superalloys of directional crystallization

Journal of Achievements of Materials and Manufacturing Engineering ◽

10.5604/01.3001.0014.6324 ◽

2020 ◽

Vol 1 (102) ◽

pp. 5-15

Author(s):

O.A. Glotka

Keyword(s):

Design Methodology ◽

Chemical Elements ◽

Multicomponent System ◽

Alloying Elements ◽

Heat Resistant ◽

Distribution Of Elements ◽

Minimum Number ◽

Essential Problem ◽

Practical Implications ◽

Thermodynamic Processes

Purpose: The specifics of the influence of alloying elements on the chemical composition of various types of carbides, their topology and morphology for a multicomponent system of the type Ni-5Cr-9Co-6Al-1Ti-11.7W-1.1Mo-1.6Nb-0.15C using the calculation method CALPHAD. It is shown that the obtained dependences closely correlate with thermodynamic processes occurring in the system. Design/methodology/approach: This work presents the results of studies of the distribution of chemical elements in the composition of carbides, depending on their content in the system. Findings: It was found that the influence of alloying elements on the composition of carbides is complex and is described by complex. Research limitations/implications: An essential problem is the prediction of the structure and properties of heat-resistant alloys without or with a minimum number of experiments. Practical implications: The obtained dependences can be used both for designing new heat-resistant alloys and for improving the compositions of industrial alloys. Originality/value: The value of this work is that the obtained dependences of the influence of alloying elements on the dissolution (precipitation) temperatures and the distribution of elements in carbides in the alloy of the Ni-5Cr-9Co-6Al-1Ti-11.7W-1.1Mo-1.6Nb-0.15C.

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X-ray mapping without STEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017027x ◽

1994 ◽

Vol 52 ◽

pp. 508-509

Author(s):

Judith M. Brock ◽

Max T. Otten

Keyword(s):

Life Science ◽

Materials Science ◽

Chemical Elements ◽

Full Description ◽

Scanning System ◽

Elemental Distribution ◽

X Ray ◽

Transmission Electron ◽

Distribution Of Elements ◽

Made In

A knowledge of the distribution of chemical elements in a specimen is often highly useful. In materials science specimens features such as grain boundaries and precipitates generally force a certain order on mental distribution, so that a single profile away from the boundary or precipitate gives a full description of all relevant data. No such simplicity can be assumed in life science specimens, where elements can occur various combinations and in different concentrations in tissue. In the latter case a two-dimensional elemental-distribution image is required to describe the material adequately. X-ray mapping provides such of the distribution of elements.The big disadvantage of x-ray mapping hitherto has been one requirement: the transmission electron microscope must have the scanning function. In cases where the STEM functionality – to record scanning images using a variety of STEM detectors – is not used, but only x-ray mapping is intended, a significant investment must still be made in the scanning system: electronics that drive the beam, detectors for generating the scanning images, and monitors for displaying and recording the images.

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Advanced test of the model stellar atmospheres: the nature of the light variability of magnetic chemically peculiar stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921308023181 ◽

2008 ◽

Vol 4 (S252) ◽

pp. 347-348

Author(s):

J. Krtička ◽

Z. Mikulášek ◽

J. Zverko ◽

J. Žižňovský ◽

P. Zvěřina

Keyword(s):

Chemical Elements ◽

Horizontal Distribution ◽

Stellar Atmospheres ◽

Silicon Iron ◽

Surface Distribution ◽

Chemically Peculiar ◽

Peculiar Stars ◽

Distribution Of Elements ◽

Chemically Peculiar Stars ◽

Light Variability

AbstractThe magnetic chemically peculiar stars exhibit both inhomogeneous horizontal distribution of chemical elements on their surfaces and the light variability. We show that the observed light variability of these stars can be successfully simulated using models of their stellar atmospheres and adopting the observed surface distribution of elements. The most important elements that influence the light variability are silicon, iron, and helium.

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Influence of alloying systems on the properties of single crystal nickel-based superalloys

International Journal of Materials Research (formerly Zeitschrift fuer Metallkunde) ◽

10.1515/ijmr-2021-8328 ◽

2021 ◽

Vol 112 (10) ◽

pp. 794-799

Author(s):

Alexander Glotka ◽

Vadim Ol’shanetskii

Keyword(s):

Single Crystal ◽

Regression Models ◽

Strength Properties ◽

Term Limits ◽

Alloying Elements ◽

Structure Stability ◽

Plastic Properties ◽

Crystal Lattices ◽

Predictive Regression ◽

First Time

Abstract The purpose of the investigation was to obtain the predictive regression models that help correct the calculation of the mechanical properties of single crystal nickel-based superalloys without conducting prior experiments. The paper considers the influence of alloying elements on their tendency to form phases in foundry nickel-based superalloys. Using the elements influence on the phase formation, the coefficient Kc’ of the ratio of alloying elements for this class of alloys was set for the first time. We have revealed the short correlation of the ratio Kc’ with the dimensional misfit of γ and γ’ crystal lattices. Also, a high probability to predict the misfit for multicomponent nickel systems is shown, which significantly affected the strength properties. The regression models of correlation dependencies on the dimensional γ/γ’- misfit were offered to predict the short-term and long-term limits of the strength of alloys. We determined the operating temperature at which the misfit value should decrease to zero. The structure stability should increase because of the structural stresses minimizing. This has a positive effect on strength and plastic properties.

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Simulation of the External Pressure Influence on the Micro-Structural Evolution of a Single Crystal Ni-Based Superalloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.278.247 ◽

2011 ◽

Vol 278 ◽

pp. 247-252

Author(s):

Inmaculada Lopez-Galilea ◽

Stephan Huth ◽

Suzana Gomes Fries ◽

Ingo Steinbach ◽

Werner Theisen

Keyword(s):

Single Crystal ◽

Microstructural Evolution ◽

Phase Field ◽

Structural Evolution ◽

Field Method ◽

External Pressure ◽

Experimental Results ◽

Alloying Elements ◽

Phase Field Method

The phase field method has been applied to simulate the microstructural evolution of a commercial single crystal Ni-based superalloy during both, HIP and annealing treatments. The effects of applying high isostatic pressure on the microstructural evolution, which mainly retards the diffusion of the alloying elements causing the loss of the orientational coherency between the phases is demonstrated by the simulation and experimental results

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A study on structural, optical, thermal and electrical properties of the amaranth dye-doped KHOOD single crystal

International Journal of Modern Physics B ◽

10.1142/s0217979220500022 ◽

2019 ◽

Vol 34 (04) ◽

pp. 2050002 ◽

Cited By ~ 1

Author(s):

K. Mahendra ◽

N. K. Udayashankar

Keyword(s):

Single Crystal ◽

Crystal Surface ◽

Photon Absorption ◽

Structural Studies ◽

Dye Molecules ◽

Optical Studies ◽

Distribution Of Elements ◽

Potassium Hydrogen ◽

Thermal And Electrical Properties ◽

Dye Molecule

Influence of amaranth dye on the potassium hydrogen oxalate oxalic acid dihydrate (KHOOD) single crystal is investigated. The structural studies were carried out to understand the crystal behavior after dye incorporation. Optical studies were performed to investigate the photon absorption of the crystal with or without the presence of dye molecule. The absorption of pure crystals were also compared with that of amaranth dye-doped crystals and the bandgap was estimated. The surface morphology and the presence of dye molecules are investigated using scanning electron microscope (SEM) and EDX analysis. The elemental mapping was carried out to understand the distribution of elements in the crystal surface. The thermal behavior of the crystal was studied and compared with that of KHOOD and dye-doped KHOOD crystals in detail. The emission properties of the crystals were studied and compared crystal. Field-dependent [Formula: see text]–[Formula: see text] studies were performed to study the conductivity of the crystals and results were discussed in detail.

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Directional Migration Behavior of Alloying Elements in the Rafting Process of the Single Crystal Superalloy DD6

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(16)30110-2 ◽

2016 ◽

Vol 45 (5) ◽

pp. 1147-1151 ◽

Cited By ~ 2

Author(s):

Zhang Shiming ◽

Yu Jingui ◽

Huang Zeyin ◽

Huang Rong ◽

Liu Shengfa ◽

...

Keyword(s):

Single Crystal ◽

Single Crystal Superalloy ◽

Alloying Elements ◽

Migration Behavior ◽

Directional Migration

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Effect of HIP Parameters on the Micro-Structural Evolution of a Single Crystal Ni-Based Superalloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.278.72 ◽

2011 ◽

Vol 278 ◽

pp. 72-77 ◽

Cited By ~ 5

Author(s):

Inmaculada Lopez-Galilea ◽

Stephan Huth ◽

Marion Bartsch ◽

Werner Theisen

Keyword(s):

Single Crystal ◽

Atmospheric Pressure ◽

High Pressures ◽

Hot Isostatic Pressing ◽

Structural Evolution ◽

Local Deformation ◽

Local Distribution ◽

Slow Cooling ◽

Distribution Of Elements ◽

Hardened State

For reducing the porosity of single crystal (SX) nickel-based superalloys, Hot Isostatic Pressing (HIP) is used. High pressures of about 100-170 MPa lead to local deformation, which close the pores. However, since HIP also requires high temperatures (1000-1200°C) it has a pronounced effect on the microstructure and the local distribution of elements. This contribution analyses the effect of different HIP treatments on both the microstructure and the segregation of the SX superalloy LEK94 in the as-precipitation-hardened state. In addition, the effects of rapid or slow cooling are analyzed. To distinguish the effect of pressure from those of temperature, the HIPed samples are compared with specimens annealed at atmospheric pressure.

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