• Korean Journal of Materials Research
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• v.13 no.12
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• pp.791-795
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• 2003

The oxidation behaviour of Fe-XAl-0.1Y(X= 5, 10, 14 wt.%) alloys were investigated at 1073, 1173 and 1273 K in oxygen/ nitrogen gas atmosphere for 1∼24 hrs using SEM/EDX, XRD and EPMA. The weight changes of Fe-XAl-0.1Y alloys followed the parabolic rate law. Oxidation rates of 10Al and 14Al alloys were ten times lower than that of 5Al alloys. This is attributed to the formations of protective $A1_2$$O_3$oxides on the surface of 10Al and 14Al alloys. The oxidation product scales of the 5Al alloy showed that thick iron oxide scales($Fe_2$$O_3$, $Fe_3$$O_4$) containing porosities formed during early stages of oxidation. With continued oxidation, aluminum oxide was formed at the alloy/scale interface.

• Journal of the Korean institute of surface engineering
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• v.24 no.3
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• pp.151-161
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• 1991

The isothermal oxidation behaviour of commercial superalloys produced in Korea was investigated by using Cahn-2000 microbalance in air at $1000^{\circ}C$ and $1100^{\circ}C$. The effect of alloying elements on the isothermal oxidation was studied by examination of the oxide structures, their morphologies, and EDS linescanning and mapping of cross-section of oxidized specimens. Generally, external Cr2O3 films were formed on all alloy surface, but were not pure, The effect on the oxidation behaviour of refractory elements such as Nb, Mo in Inconel 718 was considered to be deleterious, and the formation of internal Al oxide in Inconel 601 was beneficial.

• Nuclear Engineering and Technology
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• v.54 no.10
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• pp.3778-3787
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• 2022

The stress-assisted oxidation behaviour of Inconel 52 M/316 austenitic stainless-steel (SS) dissimilar weld joints (DMWJ) in a simulated pressurised water reactor environment was investigated. A corrosion galvanic couple formed between the Inconel 52 M and 316 SS due to differences in their nonferrous metal content. The electric field from the corrosion couple attracted metal cations (e.g. Fe²⁺, Cr³⁺) to the Inconel 52 M that were deposited as FeCr₂O₄. An additional corrosion galvanic couple was generated due to variations in the plastic deformation of the DMWJ. The superposition of electric fields from the different couples resulted in ridge-like oxide depositions in the fusion zone.

• Bulletin of the Korean Chemical Society
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• v.13 no.5
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• pp.547-550
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• 1992

The oxidation of benzaldehyde, 3,4-dimethoxy benzaldehyde, p-methoxy benzaldehyde, m-$NO_2$-benzaldehyde, and m-chlorobenzaldehyde by pyridinium chlorochromate (Corey's reagent) are reported. Michaelis-Menten behaviour is observed. The rate determining step appears to be the decomposition of a complex of benzaldehyde with PCC either through a loss of $H^+$ or $H^-$ ions.

• Journal of Electrochemical Science and Technology
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• v.7 no.2
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• pp.91-96
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• 2016

Oxidation behaviours of ash free coal (AFC), carbon, and H₂ fuels were investigated with a coin type molten carbonate fuel cell. Because AFC has no electrical conductivity, its oxidation occurs via gasification to H₂ and CO. An interesting behaviour of mass transfer resistance reduction at higher current density was observed. Since the anode reaction has the positive reaction order of H₂, CO₂ and H₂O, the lack of CO₂ and H₂O from AFC results in a significant mass transfer resistance. However, the anode products of CO₂ and H₂O at higher current densities raise their partial pressure and mitigate the resistance. The addition of CO₂ to AFC reduced the resistance sufficiently, thus the resistance reduction at higher current densities did not appear. Electrochemical impedance results also indicate that the addition of CO₂ reduces mass transfer resistance. Carbon and H₂ fuels without CO₂ and H₂O also show similar behaviour to AFC: mass transfer resistance is diminished by raising current density and adding CO₂.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.107-107
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• 1998

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.36-36
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• 2002

• Advances in aircraft and spacecraft science
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• v.3 no.2
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• pp.171-195
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• 2016

The present paper is a review of the main activities carried out within the context of the COMPTINN' program, a joint research project founded by a FUI program (Fonds $Unifi{\acute{e}}s$ $Interminist{\acute{e}}riels$) in which four research teams focused on the thermo-oxidation behaviour of HTS-TACTIX carbon-epoxy composite at 'high' temperatures ($120^{\circ}C-180^{\circ}C$). The scientific aim of the COMPTINN' program was to better identify, with a multi-scale approach, the link between the physico-chemical mechanisms involved in thermo-oxidation phenomena, and to provide theoretical and numerical tools for predicting the mechanical behaviour of aged composite materials including damage onset and development.

• The Korean Journal of Ceramics
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• v.5 no.2
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• pp.155-161
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• 1999

The tribological behaviour of monolithic SiC as well as SiC-TiC and SiC-TiC-$TiB_2$ particulate composite materials has been investigated in unlubricated oscillating sliding tests against $Al_2O_3$ at temperature in the range from room temperature up to $600^{\circ}C$. At temperatures below $600^{\circ}C$ the wear rate of the systems with the composite materials was up to 20 times lower than the wear of the $Al_2O_3$/SiC system and was dominated by the oxidation of the titanium phases. At $600^{\circ}C$ the oxidation rate of the TiC and -TEX>$TiB_2$ grains becomes predominant resulting in an enhanced wear rate of the composite rate of the TiC and TiB2 grains becomes predominant resulting in an enhanced wear rate of the composite materials. The coefficient of friction shows similar values for all materials of investigation, increasing from 0.25…0.3 at room temperature to 0.7…0.8 $600^{\circ}C$. The wear of the $Al_2O_3$/SiC system is mainly abrasive at temperatures above room temperature and is characterised by an enhanced wear of the alumina ball at $600^{\circ}C$.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.922-923
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• 2004