A Chemical-State-Specific Study of the Composition of the Natural Oxide Layer of V$_{25}$Cr$_{40}$Ti$_{35}$

The effect of plastic deformation applied to AISI 316L in low-temperature vacuum carburizing without surface activation was investigated. To create a difference in the deformation states of each specimen, solution and stress-relieving heat treatment were performed using plastically deformed AISI 316L, and the deformation structure and the carburized layer were observed with EBSD and OM. The change in lattice parameter was confirmed with XRD, and the natural oxide layers were analyzed through TEM and XPS. In this study, the carburized layer on the deformed AISI 316L was the thinnest and the dissolved carbon content of the layer was the lowest. The thickness and composition of the natural oxide layer on the surface were changed due to the deformed structure. The natural oxide layer on the deformed AISI 316L was the thickest, and the layer was formed with a bi-layer structure consisting of an upper Cr-rich layer and a lower Fe-rich layer. The thick and Cr-rich oxide layer was difficult to decompose due to the requirement for lower oxygen partial pressure. In conclusion, the oxide layer is the most influential factor, and its thickness and composition may determine carburizing efficiency in low-temperature vacuum carburizing without surface activation.

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Analyses about the influence of the natural oxide layer of aluminium on the brazeability in a shielding gas furnace

Welding in the World ◽

10.1007/s40194-013-0031-9 ◽

2013 ◽

Vol 57 (4) ◽

pp. 449-455 ◽

Cited By ~ 3

Author(s):

Julia Zähr ◽

Hans-Jürgen Ullrich ◽

Steffen Oswald ◽

Matthias Türpe ◽

U. Füssel

Keyword(s):

Oxide Layer ◽

Shielding Gas ◽

Natural Oxide Layer ◽

Natural Oxide

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Surface Characterization of the Milled–Silicon Nitride Nano Powders by XPS and TEM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.326-328.409 ◽

2006 ◽

Vol 326-328 ◽

pp. 409-412

Author(s):

Dae Chul Park ◽

Toyohiko Yano ◽

Sae Hoon Kim ◽

Won Youl Choi ◽

Jung Hee Cho

Keyword(s):

Silicon Nitride ◽

Ball Milling ◽

Oxide Layer ◽

Surface Characterization ◽

Milling Time ◽

Milling Process ◽

Chemical State ◽

Si3n4 Powder ◽

Ball Milling Time

We studied the surface characterization of milled–silicon nitride nano-powders by XPS and TEM. The change of the chemical state and morphology of the oxide layer on the surface of Si3N4 nano-particles before and after a conventional wet–ball–milling process are investigated by X–ray photoelectron spectroscopy for measuring the chemical state of the oxide layer and transmission electron microscopy for observing surface morphology. The native oxide layers of as-received Si3N4 powders confirmed by HREM observation and their chemical states were different each other. As increasing ball–milling time, the chemical composition and the volume of oxide layer in Si3N4 powders were changed. The chemical state of as–received Si3N4 powder was near to SiO2 phase. After ball–milling process for long time, that of the milled Si3N4 powder shifted to Si2N2O phase. As increasing ball-milling time, the oxide layer of Si3N4 powder was also increased.

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Nanomorphology of Aluminum Oxide Layer after Argon Ion Bombardment

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.32.60 ◽

2015 ◽

Vol 32 ◽

pp. 60-65

Author(s):

Oleg Ashkhotov ◽

Irina Ashkhotova

Keyword(s):

Oxide Layer ◽

Ion Beam ◽

Polycrystalline Aluminum ◽

Natural Oxide ◽

Argon Ion Bombardment ◽

Argon Ions ◽

Nitrogen Ion ◽

Aluminum Oxide Layer ◽

Electron Energy Loss ◽

Argon Ion

Auger electron spectroscopy (AES) and electron energy loss spectroscopy (EELS) studied the interaction of argon ions with a natural oxide layer of polycrystalline aluminum. It was found that the bombardment of argon ions with an energy lower sputtering threshold Al2O3leads to accumulation of ions bombarding the interstitial voids in the surface, thereby forming a solid solution of atoms of the target, the argon ions and nitrogen ion beam, the captured residual gas from the chamber of the spectrometer.

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Dynamic Behavior of a Silicon Oxide Layer on Silicon Ultrafine Particles

Surface Review and Letters ◽

10.1142/s0218625x03004986 ◽

2003 ◽

Vol 10 (02n03) ◽

pp. 361-364

Author(s):

Yuki Kimura ◽

Hiroshi Ueno ◽

Hitoshi Suzuki ◽

Takeshi Sato ◽

Toshiaki Tanigaki ◽

...

Keyword(s):

High Temperature ◽

Oxide Layer ◽

Ultrafine Particles ◽

Room Temperature ◽

Silicon Oxide ◽

Silicon Oxide Layer ◽

Transmission Electron ◽

Natural Oxide ◽

High Temperature Stage ◽

Amorphous Silicon Oxide

In order to clarify the high-temperature behavior of a silicon oxide layer on the surface of Si ultrafine particles, the oxide layer has been studied using the atomic-resolution high-temperature stage of a transmission electron microscope. The natural oxide layer grown on Si ultrafine particles by exposure to air was an amorphous silicon oxide layer with a thickness of 1.5 nm. This oxide layer started to dissolve into the Si crystal upon heating at 500°C, and was fully dissolved into the Si crystal at 600°C in vacuum. When the specimen was cooled back to room temperature, the silicon oxide layer reappeared on the Si surface. This phenomenon, which can be detected only at high temperatures, is presented in this paper.

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The Features of the Current-Voltage Characteristics of Field Emission Metal Cathode Covered by a Nanometer Oxide Layer

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.247.47 ◽

2016 ◽

Vol 247 ◽

pp. 47-53 ◽

Cited By ~ 1

Author(s):

Vladimir A. Bespalov ◽

Nikolay A. Djuzhev ◽

Maksim A. Makhiboroda ◽

Gleb D. Demin

Keyword(s):

Oxide Layer ◽

Field Emission ◽

Electric Fields ◽

Electron Model ◽

Current Increase ◽

Current Voltage ◽

Free Electron Model ◽

Metal Cathode ◽

Natural Oxide ◽

Current Voltage Characteristics

Based on the Sommerfeld free-electron model, the specifics of field emission from metal cathode covered by nanometer oxide layer into vacuum was theoretically studied by the example of systems «W-WO3-vacuum» and «Al-Al2O3-vacuum». The significant influence of natural oxide on the current-voltage (CV) characteristics in the region of strong electric fields (more than 107 V/cm) was investigated, where the transition to the faster current increase in the terms of Fowler-Nordheim (FN) coordinates occurs. At low electric fields (less than 107 V/cm) the CV characteristics may be described by the FN formula for the emission current and can be used to estimate the effective barrier height, which is important in selecting a good cathode material.

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Effect of Fluoride Addition in Sulfuric Acid-Based Desmutting Solution for Aluminium Alloy AA8006

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.813.285 ◽

2019 ◽

Vol 813 ◽

pp. 285-291

Author(s):

Anna Carangelo ◽

Annalisa Acquesta ◽

Francesco Bravaccino ◽

Ciro Sinagra ◽

Tullio Monetta

Keyword(s):

Sulfuric Acid ◽

Aluminium Alloy ◽

Oxide Layer ◽

Industrial Process ◽

Optical Emission ◽

Emission Spectrometry ◽

Potentiodynamic Curves ◽

Natural Oxide ◽

Pre Treatment ◽

Performance Surface

Aluminium alloys are covered spontaneously by a natural oxide layer, well adherent to the surface. For improving the material’s anticorrosion performance surface pre-treatments are needed in order to remove the superficial oxide and to prepare the alloy surface to subsequent treatments. The pre-treatment process involves several steps, including desmutting. The last requires the immersion of the part in an appropriate solution, typically composed of several chemicals, able to remove the oxide layer. In this work, the effect of the fluorides addition into a sulfuric acid-based solution, when used in a desmutting industrial process, was evaluated. Potentiodynamic curves, glow discharge optical emission spectrometry and contact angle techniques were used to characterize the surface of the aluminium alloy AA8006 after desmutting.

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Structural changes in silicon-on-insulator material during post-implantation annealing

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145054 ◽

1986 ◽

Vol 44 ◽

pp. 736-737

Author(s):

C. O. Jung ◽

S. J. Krause ◽

S.R. Wilson

Keyword(s):

Integrated Circuits ◽

Oxide Layer ◽

High Speed ◽

Structural Changes ◽

Device Fabrication ◽

Silicon On Insulator ◽

High Quality ◽

Radiation Hardened ◽

Post Implantation ◽

Very High

Silicon-on-insulator (SOI) structures have excellent potential for future use in radiation hardened and high speed integrated circuits. For device fabrication in SOI material a high quality superficial Si layer above a buried oxide layer is required. Recently, Celler et al. reported that post-implantation annealing of oxygen implanted SOI at very high temperatures would eliminate virtually all defects and precipiates in the superficial Si layer. In this work we are reporting on the effect of three different post implantation annealing cycles on the structure of oxygen implanted SOI samples which were implanted under the same conditions.

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