The Effect of Water Vapor on Thermal Oxide Grown on Inconel 690

Nickel based alloys are well considered materials for uses in high temperature applications. Inconel 690 is the one of outstanding candidate with the superior properties. The aim of this report is to present the influence of water vapor on thermal oxide film. Inconel 690 was oxidized under dry and wet atmosphere at 900°C for 30 hours. The oxidized samples were characterized by SEM/EDS, Raman spectroscopy, and photoelectrochemical technique. The results illustrated that typical thermal oxides grown on alloy composed of Cr, Fe, Ni, in forms of Cr2O3, NiFe2O4, NiCr2O4, Fe2O3, Fe2–xCrxO3and/or solid solution of NiFe2O4−NiCr2O4. The presence of water vapor affected on oxide morphology, its stoichiometry, and also semiconducting behavior. Oxide film grown under water vapor atmosphere show the homogeneity. Water vapor promoted the predominated oxide of Cr2O3with n−type semiconducting. Moreover the characterization revealed the effect of surface orientation on oxidation mechanism in case of sample which oxidized in oxygen atmosphere.

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Evolution of Oxide Film of T91 Steel in Water Vapor Atmosphere at 750 °C

Oxidation of Metals ◽

10.1007/s11085-013-9448-1 ◽

2013 ◽

Vol 81 (3-4) ◽

pp. 383-392 ◽

Cited By ~ 9

Author(s):

Guangming Liu ◽

Caifu Wang ◽

Fei Yu ◽

Jihong Tian

Keyword(s):

Water Vapor ◽

Oxide Film ◽

Water Vapor Atmosphere

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Oxidation Behavior of T91 Steel in Water Vapor Atmosphere at 750°C

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.941-944.193 ◽

2014 ◽

Vol 941-944 ◽

pp. 193-197

Author(s):

Guang Ming Liu ◽

Cai Fu Wang ◽

Gang Liu ◽

Zhi Lei Liu ◽

Ji Hong Tian

Keyword(s):

Water Vapor ◽

Oxidation Behavior ◽

Early Stage ◽

Oxidation Mechanism ◽

Sample Surface ◽

Mass Gain ◽

Initial Stage ◽

Oxidation Stage ◽

Water Vapor Atmosphere ◽

Gain Stage

The oxidation behavior of T91 steel in Ar-10%H2O atmosphere at 750°C was investigated. The morphology, microstructures and composition of oxide scales were examined by SEM/EDS and XRD. The results showed that the oxidation kinetics followed logarithmic law in the initial stage and parabolic law in the latter stage. At the early stage Cr-rich oxide film formed on the sample surface, which led to slow mass gain stage. In the latter oxidation stage, Fe ions diffused outward, resulting in fast oxidation stage. The oxidation scales consisted of two layers, an porous Fe2O3outer layer and an denser Cr-rich inner layer. Some cracks were formed between the inner and outer layers. The oxidation mechanism of T91 in water-vapor atmosphere at high temperature was discussed in brief.

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Influence of Water Vapor and Temperature on the Oxide Scale Growth and Alpha-Case Formation in Ti-6Al-4V Alloy

Oxidation of Metals ◽

10.1007/s11085-021-10088-x ◽

2021 ◽

Author(s):

B. Öztürk ◽

L. Mengis ◽

D. Dickes ◽

U. Glatzel ◽

M. C. Galetz

Keyword(s):

Water Vapor ◽

Oxide Scale ◽

Oxidation Behavior ◽

Subsurface Layer ◽

Oxygen Enrichment ◽

Oxide Morphology ◽

Dry Air ◽

Subsurface Zone ◽

Alpha Case ◽

Influence Of Water

AbstractThe Ti-6Al-4V alloy is extensively used in aerospace, automotive and biomaterial applications. In the aerospace industry, the service temperature of Ti-6Al-4V is currently limited to 350 °C due to its insufficient oxidation resistance. Oxidation at higher temperatures causes the formation of a fast-growing oxide scale and an oxygen-enriched subsurface layer, which is known as the “alpha-case.” Additionally, the effect of water vapor on the oxidation behavior is critical. In the present study, the oxidation behavior of Ti-6Al-4V in dry air and air containing 10 vol.% H2O at 500, 600 and 700 °C for up to 500 h has been investigated. The main focus of this study is the examination of the different oxide scale morphologies along with the oxygen enrichment in the subsurface zone. It has been observed that spallation of the oxide scale is more severe in a water vapor-containing environment. In dry air, the oxide morphology shows the typical layered TiO2/Al2O3 structure after exposure at 700 °C for 300 h, while Al2O3 precipitates are present in the outermost part of the TiO2 scale when oxidized in wet air. This indicates that the solubility and diffusivity of Al3+ ions in TiO2 are influenced by water vapor. In addition, the extent of oxygen enrichment in the subsurface zone (alpha-case) as a function of temperature and time is determined by nanoindentation profiles. It was shown that in contrast to the scale formation, the alpha-case thickness is not affected by the presence of water vapor in the atmosphere.

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Influence of Water Vapor on Oxide Scale Morphology of Incoloy800HT at 850°C

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.875.36 ◽

2018 ◽

Vol 875 ◽

pp. 36-40 ◽

Cited By ~ 3

Author(s):

Anusara Srisrual ◽

Kasidet Pitaksakorn ◽

Piyorose Promdirek

Keyword(s):

Raman Spectroscopy ◽

Water Vapor ◽

Oxide Scale ◽

Surface Finishing ◽

Scale Morphology ◽

Spinel Oxide ◽

Thermal Oxide ◽

Influence Of Water ◽

Oxide Phases ◽

Oxygen Gas

This paper aims to report the influence of water vapor on thermal oxide scale grown on incoloy800HT at 850°C. Alloy was prepared in coupons with a surface finishing up to 1200 SiC abrasive paper. Oxidization was performed in tubular furnace at 850°C during 50 hours. The oxidizing gases were varied as a dry oxygen gas and a wet oxygen gas. Thermal oxide morphology was characterized by scanning electron microscopy (SEM). Oxide phases were identified by X-ray diffraction (XRD) and Raman spectroscopy techniques. The oxide multilayers were revealed in all the oxidized samples. Oxide spallation was obviously detected on the samples oxidized under a dry oxygen gas, whereas, the spallation was not detected on the samples oxidized under a wet oxygen gas. Moreover, by water vapor mixing gas, the alloy surface presented a finer oxide. XRD and Raman spectroscopy provided the coincident oxide identification results. The corundum oxide of (Fe,Cr)2O3and the spinel oxide of (Fe,Cr)3O4were identified as a typical thermal oxide, however, the oxides were different in stoichiometry. The existence of water vapor promoted a Cr2O3corundum oxide, whereas, a Fe3O4spinel oxide was hindered from the outer oxide layer. Hence, water vapor not only clearly influenced on oxide scale morphology but also affected on stoichiometry of (Fe,Cr)2O3and (Fe,Cr)3O4solid solution.

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In-situ NiO nanostructure growth during heating in water vapor atmosphere

Microscopy and Microanalysis ◽

10.1017/s1431927621007595 ◽

2021 ◽

Vol 27 (S1) ◽

pp. 2102-2103

Author(s):

Boyi Qu ◽

Klaus van Benthem

Keyword(s):

Water Vapor ◽

Water Vapor Atmosphere

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Oxidation Behavior of Maraging 300 Alloy Exposed to Nitrogen/Water Vapor Atmosphere at 500 °C

Metals ◽

10.3390/met11071021 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1021

Author(s):

Mauro Andres Cerra Florez ◽

Gemma Fargas Ribas ◽

Jorge Luiz Cardoso ◽

Antonio Manuel Mateo García ◽

Joan Josep Roa Rovira ◽

...

Keyword(s):

Water Vapor ◽

Oxide Layer ◽

Magnetic Layer ◽

Adhesive Force ◽

Point Of View ◽

Maraging Steels ◽

Cobalt Spinel ◽

Water Vapor Atmosphere ◽

Iron Nickel ◽

Ferrite Cobalt

Aging heat treatments in maraging steels are fundamental to achieve the excellent mechanical properties required in several industries, i.e., nuclear, automotive, etc. In this research, samples of maraging 300 alloy were aged using a novel procedure that combines different steps with two atmospheres (nitrogen and water vapor) for several hours. The oxidized surface layer was chemical, microstructural and micromechanically characterized. Due to the thermodynamic and kinetic conditions, these gases reacted and change the surface chemistry of this steel producing a thin iron-based oxide layer of a homogeneous thickness of around 500 nm. Within the aforementioned information, porosity and other microstructural defects showed a non-homogeneous oxide, mainly constituted by magnetite, nickel ferrite, cobalt ferrite, and a small amount of hematite in the more external parts of the oxide layer. In this sense, from a chemical point of view, the heat treatment under specific atmosphere allows to induce a thin magnetic layer in a mixture of iron, nickel, and cobalt spinel ferrites. On the other hand, the oxide layer presents an adhesive force 99 mN value that shows the capability for being used for tribological applications under sliding contact tests.

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Analytical solution of one-dimensional Pennes’ bioheat equation

Open Physics ◽

10.1515/phys-2020-0197 ◽

2020 ◽

Vol 18 (1) ◽

pp. 1084-1092

Author(s):

Hongyun Wang ◽

Wesley A. Burgei ◽

Hong Zhou

Keyword(s):

Analytical Solution ◽

Radiofrequency Energy ◽

Bioheat Equation ◽

Surface Cooling ◽

One Dimensional ◽

The Fourier Transform ◽

The One ◽

Parameter Values ◽

Mathematical Derivation ◽

Effect Of Surface

Abstract Pennes’ bioheat equation is the most widely used thermal model for studying heat transfer in biological systems exposed to radiofrequency energy. In their article, “Effect of Surface Cooling and Blood Flow on the Microwave Heating of Tissue,” Foster et al. published an analytical solution to the one-dimensional (1-D) problem, obtained using the Fourier transform. However, their article did not offer any details of the derivation. In this work, we revisit the 1-D problem and provide a comprehensive mathematical derivation of an analytical solution. Our result corrects an error in Foster’s solution which might be a typo in their article. Unlike Foster et al., we integrate the partial differential equation directly. The expression of solution has several apparent singularities for certain parameter values where the physical problem is not expected to be singular. We show that all these singularities are removable, and we derive alternative non-singular formulas. Finally, we extend our analysis to write out an analytical solution of the 1-D bioheat equation for the case of multiple electromagnetic heating pulses.

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Evaluation of Li mass loss from Li2TiO3 with excess Li pebbles in water vapor atmosphere

Fusion Engineering and Design ◽

10.1016/j.fusengdes.2018.02.032 ◽

2018 ◽

Vol 136 ◽

pp. 362-366 ◽

Cited By ~ 2

Author(s):

Kazunari Katayama ◽

Haruaki Sakagawa ◽

Tsuyoshi Hoshino ◽

Satoshi Fukada

Keyword(s):

Water Vapor ◽

Mass Loss ◽

Water Vapor Atmosphere

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Actinometry at resorts

Kazan medical journal ◽

10.17816/kazmj54590 ◽

1938 ◽

Vol 34 (2) ◽

pp. 208-208

Author(s):

N. I. Kalitin

Keyword(s):

Water Vapor ◽

Solar Radiation ◽

Scattered Radiation ◽

Radiant Energy ◽

Influence Of Water

Biomedgiz. Leningrad branch. 1937 208 pp. Pr. 6 rubles. 50 kopecks. The content of the book is much wider than what the reader has a right to expect, judging by its title. The book concerns not only the measurement of radiant energy and touches on not only issues of interest to doctors working in resorts. The properties of solar radiation under various conditions, the influence of water vapor, ozone, dustiness of the atmosphere, the value of scattered radiation reflected from the sky and clouds, which is usually not paid enough attention, all these and many other issues are covered in detail in the book of prof. N.I. Kalitina largely on the basis of her own long-term research.

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