SIMS/AEM Characterization of Banded Microstructures in an Ni-Cr-Fe Alloy

Ni-Cr-Fe alloys such as Alloy 600 and Alloy 690 are single phase fee alloys with excellent resistance to corrosion. Alloy 600 is generally used in a thermally-treated condition which is characterized by the intergranular precipitation of Cr-rich M7C3 and, depending upon the aging temperature, Cr-rich M23C6. These alloys are usually cast and processed by rolling or forging. These alloys can exhibit microstructures in which there are nonuniform distributions of intragranular carbides that appear as bands aligned parallel to the working direction (i.e. longitudinal) of the material. It is also possible for these materials to exhibit duplex grain sizes which can be associated with the banded carbide structure. Banded microstructures can become more prominent after further anneals. The resistance of the carbide bands to dissolution during solution annealing at temperatures up to 1150°C has prompted the further evaluation of banding in Alloy 600, specifically in terms of identifying those elements associated with the carbide bands.

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Characterization of oxide films formed on Alloy 600 and Alloy 690 in simulated PWR primary water by using hard X-ray photoelectron spectroscopy

Journal of Solid State Electrochemistry ◽

10.1007/s10008-015-2817-8 ◽

2015 ◽

Vol 19 (12) ◽

pp. 3521-3531 ◽

Cited By ~ 13

Author(s):

Shinji Fujimoto ◽

Whee-Sung Kim ◽

Masugu Sato ◽

Jin-Young Son ◽

Masatake Machida ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Oxide Films ◽

Alloy 600 ◽

X Ray ◽

Alloy 690 ◽

Primary Water

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Effects of Pb on SCC of Alloy 600 and Alloy 690 in Prototypical Steam Generator Chemistries

Materials Science Forum ◽

10.4028/www.scientific.net/msf.475-479.1387 ◽

2005 ◽

Vol 475-479 ◽

pp. 1387-1392 ◽

Cited By ~ 6

Author(s):

Jesse Lumsden ◽

Allan McIlree ◽

Richard Eaker ◽

Rocky Thompson ◽

Steve Slosnerick

Keyword(s):

Steam Generator ◽

Open Circuit Potential ◽

Film Formation ◽

Open Circuit ◽

Alloy 600 ◽

Steam Generators ◽

Film Rupture ◽

Test Environment ◽

Alloy 690 ◽

Thermally Treated

Intergranular attack/stress corrosion cracking of Alloy 600 continues to be an issue in the tube/tube support plate crevices and top of tubesheet locations of recirculating steam generators and in the upper bundle of free span superheated regions of once through steam generators (OTSG). Recent examinations of degraded pulled tubes from several plants suggest possible lead involvement in the degradation. Laboratory investigations have been performed to determine the factors influencing lead cracking in Alloy 600 and Alloy 690 steam generator tubes. The test environment is believed to be prototypical, with the addition of lead oxide, of a concentrated liquid phase existing in the pores of thin deposits on upper bundle tubes of an OTSG. Highly strained reverse U-bend specimens were tested at controlled electrochemical potentials. Maximum susceptibility was at open circuit potential, unlike cracking of Alloy 600 in caustic and acid sulfate environments where maximum susceptibility occurs when specimens are polarized above the open circuit potential. Transgranular, intergranular and mixed mode cracking was observed and in all Alloy 600 conditions tested (mill annealed, sensitized, thermally treated) while thermally treated Alloy 690 has so far resisted cracking. A film rupture/anodic dissolution model with displacement plating of Pb preceding passive film formation is consistent with the experimental observations

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Characterization of Solution-Annealed and Thermally-Treated Alloy 600 Intergranular Oxidation using Advanced Analytical Electron Microscopy

European Microscopy Congress 2016: Proceedings ◽

10.1002/9783527808465.emc2016.6701 ◽

2016 ◽

pp. 910-911

Author(s):

giacomo bertali ◽

Fabio Scenini ◽

Grace Burke

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Alloy 600 ◽

Intergranular Oxidation ◽

Analytical Electron ◽

Thermally Treated

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Electrodeposition and Characterization of Nanocrystalline Ni-Fe Alloys

Journal of Nanomaterials ◽

10.1155/2011/519274 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 28

Author(s):

R. Abdel-Karim ◽

Y. Reda ◽

M. Muhammed ◽

S. El-Raghy ◽

M. Shoeib ◽

...

Keyword(s):

Grain Size ◽

Surface Morphology ◽

Iron Content ◽

Mass Ratio ◽

Grain Sizes ◽

Maximum Value ◽

Average Grain Size ◽

Fe Alloys ◽

Short Time

Nanocrystalline Ni-Fe deposits with different composition and grain sizes were fabricated by electrodeposition. Deposits with iron contents in the range from 7 to 31% were obtained by changing the Ni2+/Fe2+mass ratio in the electrolyte. The deposits were found to be nanocrystalline with average grain size in the range 20–30 nm. The surface morphology was found to be dependent on Ni2+/Fe2+mass ratio as well as electroplating time. The grains size decreased with increasing the iron content, especially in case of short time electroplating. Increasing the electroplating time had no significant effect on grain size. The microhardness of the materials followed the regular Hall-Petch relationship with a maximum value (762 Hv) when applying Ni2+/Fe2+mass ratio equal to 9.8.

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Characterization of Serrated Grain Boundaries in Ni-Based Alloy 690

Korean Journal of Metals and Materials ◽

10.3365/kjmm.2014.52.9.695 ◽

2014 ◽

Vol 52 (9) ◽

pp. 695-704

Author(s):

Yun Soo Lim ◽

Dong Jim Kim ◽

Seong Sik Hwang

Keyword(s):

Grain Boundaries ◽

Alloy 690

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Fabrication and Characterization of Quinary High Entropy-Ultra-High Temperature Diborides

Ceramics ◽

10.3390/ceramics4020010 ◽

2021 ◽

Vol 4 (2) ◽

pp. 108-120

Author(s):

Simone Barbarossa ◽

Roberto Orrù ◽

Valeria Cannillo ◽

Antonio Iacomini ◽

Sebastiano Garroni ◽

...

Keyword(s):

High Temperature ◽

Single Phase ◽

Nominal Composition ◽

High Entropy ◽

Chemical Complexity ◽

Alternative Processing ◽

Plasma Sintering ◽

High Temperature Synthesis ◽

Spark Plasma

Due to their inherent chemical complexity and their refractory nature, the obtainment of highly dense and single-phase high entropy (HE) diborides represents a very hard target to achieve. In this framework, homogeneous (Hf0.2Nb0.2Ta0.2Mo0.2Ti0.2)B2, (Hf0.2Zr0.2Ta0.2Mo0.2Ti0.2)B2, and (Hf0.2Zr0.2Nb0.2Mo0.2Ti0.2)B2 ceramics with high relative densities (97.4, 96.5, and 98.2%, respectively) were successfully produced by spark plasma sintering (SPS) using powders prepared by self-propagating high-temperature synthesis (SHS). Although the latter technique did not lead to the complete conversion of initial precursors into the prescribed HE phases, such a goal was fully reached after SPS (1950 °C/20 min/20 MPa). The three HE products showed similar and, in some cases, even better mechanical properties compared to ceramics with the same nominal composition attained using alternative processing methods. Superior Vickers hardness and elastic modulus values were found for the (Hf0.2Nb0.2Ta0.2Mo0.2Ti0.2)B2 and the (Hf0.2Zr0.2Ta0.2Mo0.2Ti0.2)B2 systems, i.e., 28.1 GPa/538.5 GPa and 28.08 GPa/498.1 GPa, respectively, in spite of the correspondingly higher residual porosities (1.2 and 2.2 vol.%, respectively). In contrast, the third ceramic, not containing tantalum, displayed lower values of these two properties (25.1 GPa/404.5 GPa). However, the corresponding fracture toughness (8.84 MPa m1/2) was relatively higher. This fact can be likely ascribed to the smaller residual porosity (0.3 vol.%) of the sintered material.

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Synthesis and characterization of a novel single-phase sputtered Cu2O thin films: Structural, antibacterial activity and photocatalytic degradation of methylene blue

Inorganic Chemistry Communications ◽

10.1016/j.inoche.2021.108606 ◽

2021 ◽

pp. 108606

Author(s):

Mohsin Raza Dustgeer ◽

Syeda Tasmia Asma ◽

Asim Jilani ◽

Kashif Raza ◽

Syed Zajif Hussain ◽

...

Keyword(s):

Thin Films ◽

Methylene Blue ◽

Antibacterial Activity ◽

Photocatalytic Degradation ◽

Single Phase ◽

Synthesis And Characterization ◽

Cu2o Thin Films

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Characterization of CuSbSe2 crystallites synthesized using a hot injection method

RSC Advances ◽

10.1039/c6ra20692a ◽

2016 ◽

Vol 6 (101) ◽

pp. 99297-99305 ◽

Cited By ~ 7

Author(s):

Hsing-I. Hsiang ◽

Chang-Ting Yang ◽

Jui-Huan Tu

Keyword(s):

Single Phase ◽

Triethylene Glycol ◽

Reducing Agent ◽

Injection Method ◽

Hot Injection ◽

Low Toxic

In this study, a novel and facile hot injection method for the synthesis of single phase CuSbSe2 crystallites was developed by using low toxic triethylene glycol as both the solvent and reducing agent and triethylenetetramine as co-reducing agent.

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