• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.11a
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• pp.7-9
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• 2007

Thin films of CrAlSiN were deposited on SKD11 tool steel substrate using Cr and AlSi cathodes by a cathodic arc plasma deposition system. The influence of process parameters on the deposited film properties were investigated. The oxidation characteristics of the films were studied at temperatures ranging from 800 and 1000+C up to 50 h in air. The films showed superhardness and good oxidation resistance..

• Journal of the Korean Ceramic Society
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• v.31 no.7
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• pp.777-783
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• 1994

Oxidation behavior of hot-pressed silicon nitride ceramics with various sintering additives has been investigated. The weight gain of each specimens has shown in the range of 0.11 mg/$\textrm{cm}^2$ ~3.4 mg/$\textrm{cm}^2$ at 140$0^{\circ}C$ for 192 h and eleven compositions have shown good oxidation resistance with the weight gain below 0.5 mg/$\textrm{cm}^2$. The oxidation rate has been shown to obey the parabolic rate law and the oxidized surface has consisted of $\alpha$-cristobalite and M2Si2O7 or MSiO3 (M=rare earth or transition metals) phase. The oxidation rate of each specimens has related to the eutectic temperature between additive oxide and SiO2, and ionic radius of additive oxides, respectively. From the above results, it could be concluded that the oxidation behavior of hot pressed silicon nitride is dominated by the high temperature properties of grain boundary glassy phase and the high temperature properties of grain boundary glassy phase are affected by the ionic radius of additive oxides.

• Transactions of Materials Processing
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• v.8 no.3
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• pp.327-327
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• 1999

The oxidation behavior of 60%Cu-40%Zn brass haying small amounts of Zr, Cr, Mg, Al, and Si was studied between 873 and 1043 K in air. The alloying element of Mg was harmful, while other alloying elements were beneficial to oxidation resistance. Particularly, the simultaneous addition of Al and Si decreased the oxidation rate drastically. During oxidation, Zr formed ZrO₂, Cr formed CuCr₂O₄, Mg formed MgO, Al formed A1₂CuO₄, and Si formed amorphous SiO₂. These oxides were incorporated in the oxide scale composed predominantly of ZnO. The oxide scales formed on all the tested alloyswere prone to cracking, wrinkling, and spallation.

• Journal of the Korean institute of surface engineering
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• v.37 no.1
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• pp.58-63
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• 2004

The oxidation behavior of Ti-Nb alloys was studied in dry atmosphere. After vacuum arc melting and hot rolling treatment, Ti-Nb alloys were oxidized at $450^{\circ}C$∼$750^{\circ}C$. The oxidation behaviors between matrix and oxide scale were analyzed by SEM, XPS and XRD. Ti-Nb alloys had higher oxidation resistance than pure Ti at $750^{\circ}C$. XPS analysis of oxide film revealed that $TiO_2$ oxide was formed on the top of surface. The weight gains during the oxidation increase rapidly at temperature above $600^{\circ}C$ which obey the parabolic law.

• Journal of the Korean institute of surface engineering
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• v.34 no.1
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• pp.25-32
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• 2001

$TiB_2$ ceramics were oxidized at 800, 900 and $1000^{\circ}C$ in air for 40 hr, and their oxidation property was investigated using TGA, XRD, SEM and EPMA. The oxidation resistance decreased with an increase in oxidation temperature. The scale was essentially composed of $TiO_2$ only. $B_2$$O_3$ formed during oxidation escaped from the $TiO_2$ oxide scale owing to its high vapor pressure. This made the oxide scale highly porous and thick. The oxidation reaction was mainly governed by the inward transport of oxygen.$ TiO_2$ existing at the outermost scale grew into peculiarly shaped blades, as the reaction progressed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.131-132
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• 2007

An AlGaN/GaN high electron mobility transistor(HEMT) was fabricated and the effect of photoelectrochemical oxidation of AlGaN/GaN surface was investigated. The oxidation of AlGaN surface was done in water at the bias of 10 V under the deep UV light illumination. The sheet resistance of the AlGaN/GaN structure was increased and gate leakage current of the HEMT was decreased by the oxidation. However, the transconductance of the HEMT was not degraded by the oxidation.

• Journal of the Korean institute of surface engineering
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• v.39 no.1
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• pp.43-48
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• 2006

The oxidation behavior and Biocompatibility of pure Ti and Ti-8Ta-3Nb alloy were studied in dry air atmosphere. The specimens showed that Ti-8Ta-3Nb alloy had higher oxidation resistance than pure Ti at $650^{\circ}C$. Cytotoxicity test also revealed that moderate oxidation treatment lower cell toxicity and Ti-8Ta-3Nb alloy showed better results compared with pure Ti. The weight gains during the oxidation increase rapidly at temperature above $600^{\circ}C$.

• Journal of the Korean institute of surface engineering
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• v.47 no.5
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• pp.252-256
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• 2014

The TiAlCrSiN film was deposited on the WC-20%TiC-10%Co carbide, and its oxidation behavior was examined at $700-1000^{\circ}C$. It displayed relatively good oxidation resistance owing to the formation of $TiO_2$, $Al_2O_3$, $Cr_2O_3$, and $SiO_2$ up to $900^{\circ}C$. However, at $1000^{\circ}C$, the fast oxidation rate and partial oxidation of WC in the substrate led to the formation of the thick, fragile oxide scale.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.6
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• pp.335-340
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• 2003

To improve properties of wear resistance and anti-corrosion of the trivalent chromium platings, oxinitrocarbunsing and steam oxidation were conducted. Armophous trivalent Cr platings could be transformed to chromium carbides of high hardness, that showed low friction and wear rate. Even though micro-cracks were within as platings, superior anti-corrosion property was obtained by these treatments due to healing of cracks at the interface between the trivalent chromium platings and substrate.

• Tribology and Lubricants
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• v.29 no.6
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• pp.360-365
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• 2013

In this study, sliding wear tests were conducted to investigate the effects of tempered hardness on the sliding wear behavior of bearing steel. At a sliding speed of 0.3 m/s, the wear resistance of bearing steel with a tempered hardness of HRC 54 was superior to that with HRC 62. It was found that bearing steel with HRC 54 showed a strong tendency for the occurrence of oxidation wear at that speed, compared to that with HRC 62. This would be due to the troostitic structure of bearing steel with HRC 54, which is highly susceptible to corrosion. In this context, it is considered that sliding wear behavior could be affected by the corrosion resistance of the material.