Atom-probe study of the initial stage of selective oxidation of Ni from the CuNi alloy system

1991 ◽  
Vol 245 (1-2) ◽  
pp. A137
Keyword(s):  
Selective Oxidation ◽  
Alloy System ◽  
Atom Probe ◽  
Initial Stage ◽  
Ni Alloy

Atom-probe study of the initial stage of selective oxidation of Ni from the Cu-Ni alloy system

1991 ◽  
Vol 245 (1-2) ◽  
pp. 132-149 ◽  
Author(s):  
K. Hono ◽  
T. Iwata ◽  
M. Nakamura ◽  
H.W. Pickering ◽  
I. Kamiya ◽  
...  
Keyword(s):  
Selective Oxidation ◽  
Alloy System ◽  
Atom Probe ◽  
Initial Stage ◽  
Ni Alloy

Atom-Probe Study of Selective Oxidation of Ni from Cu-Ni Alloy

1989 ◽  
Vol 139 ◽  
Author(s):  
K. Hono ◽  
M. Nakamura ◽  
H. W. Pickering ◽  
T. Sakurai
Keyword(s):  
Selective Oxidation ◽  
Atom Probe ◽  
Ni Alloy

AP-FIM INVESTIGATION OF THE INITIAL STAGE OF OXIDATION ON THE SURFACE OF ALLOYS

1995 ◽  
Vol 02 (02) ◽  
pp. 177-181 ◽  
Author(s):  
D.G. REN
Keyword(s):  
Binding Energy ◽  
Field Strength ◽  
Metal Atom ◽  
Exposure Period ◽  
Atom Probe ◽  
Field Evaporation ◽  
Residual Oxygen ◽  
Metal Atoms ◽  
Initial Stage ◽  
The Difference

This paper reports a study of the initial stage of oxidation on the surface of alloys by field-ion microscopy and atom probe (AP-FIM). The samples used in this investigation contained Ni, Ni-Cr, Ni-Al, Ti-Al , and Pt-Rh metals and alloys. A clean-tip surface, after atom-probe analysis, was exposed in the atmosphere of residual oxygen (vacuum 10−4 torr) for a few hours. AP analysis found that a small quantity of oxygen was adsorbed on the surface of the alloys. The clusters of a combination of a metal atom with an oxygen, i.e., PtO +2, NiO +2, and TiO +2 were determined by AP. The experiment found that the binding energy between metal atom on the surface of alloys was reduced when oxygen was adsorbed on the surface. The binding energy of surface atoms was determined according to the field strength of the tip surface. The reduction of the binding energy was about 0.5–2.0 eV, which changed following the exposure period in the atmosphere and depending on the kind of alloys used. The difference in field-ion image due to adsorption of oxygen was observed as compared to without the oxygen. The results of the experiment show that oxygen was absorbed on the “clean surface” of alloys. First the oxygen molecule was dissociated to oxygen atoms by the reaction with metal atoms and then formed the metal-oxygen bonding (M+O→MO) . This is an initial stage of oxidation on the surface of alloys. The clusters of combining oxygen did not dissociate during the field-evaporation process with 4.5 V/Å field strength.

scholarly journals Creep Resistance of TiC-Mo2C-Ni Alloy System Affected by Oxygen Content of Alloy.

1992 ◽  
Vol 39 (11) ◽  
pp. 1025-1027
Author(s):  
Mitsuo Ueki ◽  
Satoshi Kinoshita ◽  
Hisashi Suzuki
Keyword(s):  
Oxygen Content ◽  
Creep Resistance ◽  
Alloy System ◽  
Ni Alloy

INFLUENCE OF ION IMPLANTATION ON OXIDATION BEHAVIOR OF TiAl

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4667-4672 ◽  
Author(s):  
MICHIKO YOSHIHARA ◽  
SHIGEJI TANIGUCHI
Keyword(s):  
Ion Implantation ◽  
Selective Oxidation ◽  
Oxidation Behavior ◽  
Complex Oxide ◽  
The Other ◽  
Alloying Elements ◽  
Implantation Technique ◽  
Other Hand ◽  
Initial Stage ◽  
Cu And Zn

The influence of alloying elements on oxidation behavior of TiAl has been investigated using an ion-implantation technique and the mechanisms were discussed. The influence can be classified into several groups according to their effects. The implantation of β-forming elements, halogens, Cu and Zn results in a significant improvement of the oxidation behavior through formation of Al 2 O 3 layer in the initial stage of oxidation. The improvement by Zn is attributed to the formation of complex oxide of Zn and selective oxidation of Al beneath the layer. The implantation of Al , Si or P is also effective. On the other hand, implantation of Ag , Se and other several elements enhance the oxidation. The deterioration by Ag or Se is explained in terms of Al depletion in the implanted layer.

Effects of Nitrogen and Helium Ion Implantation on Uniaxial Tensile Properties of 316 SS Foils

1983 ◽  
Vol 27 ◽  
Author(s):  
J. A. Spitznagel ◽  
B. O. Hall ◽  
N. J. Doyle ◽  
Raman Jayram ◽  
R. W. Wallace ◽  
...  
Keyword(s):  
Tensile Properties ◽  
Mechanical Response ◽  
Atom Probe ◽  
Uniaxial Tensile ◽  
Probe Field ◽  
Thin Foils ◽  
Ni Alloy ◽  
Helium Ion ◽  
Laminated Structures ◽  
Strain Responses

ABSTRACTImplantation of nitrogen into steels is known to affect surface sensitive mechanical properties. Tensile properties of thin foils implanted with either nitrogen or helium at 300 K have been measured. Fluences greater than 1 × 1016 ions/cm2 raise the yield stress and fracture stress and reduce the plastic strain to failure. Both nitrogen and helium give comparable stress-strain responses for equal average concentrations of implanted ions. The mechanical response is discussed in terms of plastic flow of laminated structures and hardening mechanisms. Initial results of atom probe field ion microscopy examinations of nitrogen implanted Fe-15 wt.% Cr-12 wt.% Ni alloy are described.

Quasicrystals in the Ti–Zr–Ni alloy system

2004 ◽  
Vol 334-335 ◽  
pp. 223-227 ◽  
Author(s):  
J.B. Qiang ◽  
Y.M. Wang ◽  
D.H. Wang ◽  
M. Kramer ◽  
P. Thiel ◽  
...  
Keyword(s):  
Alloy System ◽  
Ni Alloy

Multi Scale Characterization of Stress Corrosion Cracking of Alloy X750

2013 ◽  
Vol 1519 ◽  
Author(s):  
Kevin Fisher ◽  
Sébastien Teysseyre ◽  
Emmanuelle A Marquis
Keyword(s):  
Stress Corrosion ◽  
Stress Corrosion Cracking ◽  
Atom Probe ◽  
Corrosion Cracking ◽  
Twin Boundaries ◽  
Cracking Behavior ◽  
Multi Scale ◽  
Ni Alloy ◽  
Scale Characterization ◽  
Boundary Chemistry

ABSTRACTGrain boundary chemistry in an X750 Ni alloy was analyzed by atom probe tomography in an effort to clarify the possible roles of elemental segregation and carbide presence on the stress corrosion cracking behavior of Ni alloys. Two types of cracks are observed: straight cracks along twin boundaries and wavy cracks at general boundaries. It was found that carbides (M23C6 and TiC) are present at both twin and general boundaries, with comparable B and P segregation for all types of grain boundaries. Twin boundaries intercept γ’ precipitates while the general boundaries wave around the γ’ and carbide precipitates. Near a crack tip, oxidation takes place on the periphery of carbide precipitate.

The Strengthening Mechanism in Consolidated Rapidly Solidified Alloys

1985 ◽  
Vol 58 ◽  
Author(s):  
Monde A. Otooni
Keyword(s):  
Tensile Stress ◽  
Early Stage ◽  
Alloy System ◽  
Maximum Growth ◽  
Strengthening Mechanism ◽  
Stress Measurements ◽  
Functional Relationships ◽  
Grain Sizes ◽  
Initial Stage ◽  
Rapidly Solidified

ABSTRACTAttempts have been made to study mechanisms of strengthening in the Ni68W22C8B2 and the Ni45CO20 Cr10MO4Fe5B16 alloy systems during their amorphous crysialline transitions. In the Ni68W22C8B2 system where amorphous particulates of varying sizes have been cons Ti a ed at high pressure and low temperature (3.6 MPa, and 673°K respectively), the initial stage of crystallization is marked by transformation of the localized regions of the specimen. These crystallized regions contain microcracks and voids. Microhardness measurements from the consolidated specimens indicate an increasing trend in the microhardness with decreasing particulate sizes. Premature failures of the consolidated specimen during tensile stress measurements have been attributed to the presence of microcracks and voids in these specimens. In the Ni45Co20Crl0Mo4Fe5B16 alloy system isothermal annealing of an initially amorphous alloy has been allowed to produce grains of varying sizes. The tensile stress measurements from these thermally annealed ribbons indicate two distinctly different functional relationships between the strength, σ, and the grain size parameter, λ. In the early stage of transformation where grain reach a maximum growth of up to 400 Å, the functional form of the strength, σ, with the grain parameter, λ, is σ = σ + K Log λ, where σO and K are constants. During latter stages of transformation, where grains larger than 400 Å have been formed, the strength, σ, varies with the inverse square root of the grain sizes. This latter relationship is analogous with the well known Hall-Petch relationships, which describes the strength, σ, as a function of the grain sizes in conventionally processed alloys.

scholarly journals Effect of Stress on Spinodal Decomposition in Binary Alloys: Atomistic Modeling and Atom Probe Tomography

2021 ◽  
Author(s):  
Alexander Dahlström ◽  
Frederic Danoix ◽  
Peter Hedström ◽  
Joakim Odqvist ◽  
Helena Zapolsky
Keyword(s):  
Tensile Stress ◽  
Spinodal Decomposition ◽  
Atom Probe Tomography ◽  
Critical Phenomenon ◽  
Binary Alloys ◽  
Alloy System ◽  
Atom Probe ◽  
Stress Effect ◽  
Atomistic Modeling ◽  
Characteristic Wavelength

AbstractSelf-organizing nanostructure evolution through spinodal decomposition is a critical phenomenon determining the properties of many materials. Here, we study the influence of stress on the morphology of the nanostructure in binary alloys using atomistic modeling and atom probe tomography. The atomistic modeling is based on the quasi-particle approach, and it is compared to quantitative three-dimensional (3-D) atom mapping results. It is found that the magnitude of the stress and the crystallographic direction of the applied stress directly affect the development of spinodal decomposition and the nanostructure morphology. The modulated nanostructure of the binary bcc alloy system is quantified by a characteristic wavelength, $$ \lambda $$ λ . From modeling the tensile stress effect on the A-35 at. pct B system, we find that $$ \lambda _{001}< \, \lambda _{111}< \, \lambda _{101}< \, \lambda _{112}$$ λ 001 < λ 111 < λ 101 < λ 112 and the same trend are observed in the experimental measurements on an Fe-35 at. pct Cr alloy. Furthermore, the effect of applied compressive and shear stress states differs from the effect of the applied tensile stress regarding morphological anisotropy.

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