• 한국세라믹학회지
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• 제40권5호
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• pp.460-467
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• 2003

기계적 합금화법에 의해 준비된 복합분말을 이용하여 용사공정에 의해 알루미늄 모재에 Al-SiC$_{p}$ 복합재료 코팅층을 형성하였다. 24h milling 후 복합화된 분말을 제조할 수 있었으며, 이 분말을 용사하여 복합재료 코팅층을 형성할 수 있었다. 코팅층의 두께 및 기공율과 공정변수와 관계를 분석하였으며, 경도의 증가를 확인하였다. 또한 TEM분석에 의해 Al-Si-C-O 화합물의 존재를 확인하였다.

• 한국세라믹학회지
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• 제37권5호
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• pp.497-504
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• 2000

In this study, mullite-zirconia comosite was fabricated by adding ZrOCl2.8H2O using of boehmite gel coating to Hadong kaolin (pink A grade) in order to enhance strength of the mullite specimens. The influence of ZrOCl2.8H2O content and fireing temperature on the crystall phase, microstructure, bulk density, strength of the specimens was investigated. Mullite-zirconia composite was produced in the process of coating zirconia to mullite powder synthesized thereafter and mixing simultaneously of starting materials with boehmite-zirconia gel. Maximum strength with in this study was 251 sintered at 1$600^{\circ}C$ for 2h. Bulk density and strength of the composite with zirconia coated mullite was higher than simultaneous on mixture of starting materials.

• 한국해양공학회지
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• 제15권3호
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• pp.69-74
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• 2001

This paper was to investigate of a adhesiveness for the plasma sprayed coating materials did salt spray by acoustic emission method in tensile loadings. The powders used for the coating were nickel aluminum composite powder Ni-4.5wt.%Al and titanium dioxide powder $TiO_2$. These powders were coated on a carbon steel S45C by plasma spray method. The result solution was a 5% NaCl and the slat spray times were 2, 5 and 10 hours respectively. The salt solution penetrated into the surface of the substrate through pore of the coating layer built in the process of plasma spay. Corrosion productions formed on the surface of substrate. The adhesiveness between the substrate and the coating layer is weaken by corrosion and the exfoliation initiated chiefly at the corrosion surface of the substrate. The AE events and energy of the corroded coating specimens decreased as the salt spray times increased.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2001년도 춘계학술대회 논문집
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• pp.344-349
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• 2001

This paper was to investigate of a adhesiveness for the plasma sprayed coating materials did salt spray by acoustic emission method in tensile loadings. The powders used for the coating were nickel aluminum composite powder Ni-4,5wt.%Al and titanium dioxide powder Ti02. These powders were coated on a carbon steel S45C by plasma spray method. The salt solution was a 5% NaCl and the salt spray times were 2, 5 and 10 hours respectively. The salt solution penetrated into the surface of the substrate through pore of the coating layer built in the process of plasma spay. Corrosion productions formed on the surface of substrate. The adhesiveness between the substrate and the coating layer is weaken by corrosion and the exfoliation initiated chiefly at the corrosion surface of the substrate. The AE events and energy of the corroded coating specimens decreased as the salt spray times increased.

• 한국재료학회지
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• 제27권7호
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• pp.374-380
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• 2017

Properties of coatings produced by warm spray were investigated in order to utilize this technique as a repair method for Al tire molds. $Al-(0-10%)Al_2O_3$ composite powder was sprayed on Al substrate by warm spraying, and the microstructure and mechanical properties of the composite coating layer were investigated. For comparative study, the properties of the coating produced by plasma spray, which is a relatively high-temperature spraying process, were also investigated. The composite coating layers produced by the two spray techniques exhibited significantly different morphology, perhaps due to their different process temperatures and velocities of particles. Whereas the $Al_2O_3$ particles in the warm sprayed coating layer maintained their initial shape before the spray, flattened and irregular shape $Al_2O_3$ particles were distributed in the plasma sprayed coating layer. The coating layer produced by warm spray showed significantly higher adhesive strength compared to that produced by plasma spray. Hardness was also higher in the warm sprayed coating layer compared to the plasma sprayed one. Moreover, with increasing the fraction of $Al_2O_3$, hardness gradually increased in both spray coating processes. In conclusion, an $Al-Al_2O_3$ composite coating layer with good mechanical properties was successfully produced by warm spray.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 추계학술대회 논문집
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• pp.339-339
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• 2007

Metal coating on ceramic powder has long been attracting interest for various applications such as superconductor where the brittle nature of high temperature ceramic superconductor was complemented by silver coating and metalloceramics where mechanical property improvement was achieved via electroless plating. More recently it has become of great interest in embedded passive device applications since metal coating on ceramic particles may result in the enhancement of the dielectric properties of ceramic-polymer composite capacitors. In our study, nickel ion-containing solution was used for coating commercial capacitor-grade $BaTiO_3$ powder. After filtering process, the powder was dried and heat-treated in 5% forming gas at $900^{\circ}C$. XRD and TEM were utilized for the observation of crystallization behavior and morphology of the particles. It was found that the nickel coating characteristics were strongly dependent on the several parameters and processing variables, such as starting $BaTiO_3$ particle size, nickel source, solution chemistry, coating temperature and time. In this paper, the effects of these variables on the coating characteristics will be presented in some detail.

• 한국재료학회지
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• 제9권12호
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• pp.1205-1210
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• 1999

분무건조법으로 용사용 원적외선 세라믹/알루미늄 복합분말을 제조하여 플라즈마 용사법으로 알루미늄 모재에 용사한 후, 미세구조, 결정상, 열충격저항성 그리고 분광복사율을 조사하였다. 분무건조된 복합분말의 입형은 구형으로 34~105${\mu}m $. 영역에서 높은 복사율을 보였다. 그러나 알루미늄 첨가량이 증가할수록 원적외선 방사특성은 감소하였다. 결과적으로 용사법으로 원적외선 방사특성의 큰 손실 없이 방사체를 제조하기 위해서는 20~30%wt%Al를 첨가하여 복합분말을 제조하는 것이 가장 효율적이라고 판단된다.

• 한국재료학회지
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• 제30권7호
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• pp.350-358
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• 2020

A variety of composite powders having different aluminum and carbon contents are prepared using various organic solvents having different amounts of carbon atoms in unit volume as ball milling agents for titanium and aluminum ball milling. The effects of substrate temperature and post-heat treatment on the texture and hardness of the coating are investigated by spraying with this reduced pressure plasma spray. The aluminum part of the composite powder evaporates during spraying, so that the film aluminum content is 30.9 mass%~37.4 mass% and the carbon content is 0.64 mass%~1.69 mass%. The main constituent phase of the coating formed on the water-cooled substrate is a non-planar α₂ phase, obtained by supersaturated carbon regardless of the alloy composition. When these films are heat-treated at 1123 K, the main constituent phase becomes γ phase, and fine Ti₂AlC precipitates to increase the film hardness. However, when heat treatment is performed at a higher temperature, the hardness is lowered. The main constitutional phase of the coating formed on the preheated substrate is an equilibrium gamma phase, and fine Ti₂AlC precipitates. The hardness of this coating is much higher than the hardness of the coating in the sprayed state formed on the water-cooled substrate. When hot pressing is applied to the coating, the porosity decreases but hardness also decreases because Ti₂AlC grows. The amount of Ti₂AlC in the hot-pressed film is 4.9 vol% to 15.3 vol%, depending on the carbon content of the film.

• Journal of Advanced Marine Engineering and Technology
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• 제24권1호
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• pp.49-58
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• 2000

Thermal spraying is one of the most common surface coating techniques to be used for many applications and flame spraying covers a wide range of different materials which can be coated onto various substrates. The purpose of this study is to investigate the effects of mixed ratio in composite coatings on the mechanical and anti-corrosion properties. The five different types of composite coatings were made with $Al_2O_3$ ceramic and Ni-alloy powder on the mild steel substrate by flame spraying method. The mechanical properties such as microhardness, adhesive strength and erosion resistance and corrosion resistance were tested for the sprayed coating specimens. The results obtained are summarized as follows; 1. The composite coating layers greatly improve the microstructure, erosion resistance and adhesive strength by increasing the content of Ni-Al alloy. 2. Microhardness of the compsite coating layer is decreased by increasing the content of Ni-Al alloy. 3. The anti-corrosion properties is considerably improved by increasing the compsite rate of Ni-Al alloy.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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• pp.1142-1143
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• 2006

Kinik Company pioneered diamond pad conditioners protected by DLC barrier ($DiaShield^{(R)}$ Coating) back in 1999 (Sung & Lin, US Patent 6,368,198). Kink also evaluated Cermet Composite Coating (CCC or $C^3$, patent pending) with a composition that grades from a metallic (e.g. stainless steel) interlayer to a ceramic (e.g. $Al_2O_3$ or SiC) exterior. The metallic interlayer can form metallurgical bond with metallic matrix on the diamond pad conditioner. The ceramic exterior is both wear and corrosion resistant. The gradational design of $C^3$ coating will assure its strong adherence to the substrate because there is no weak boundary between coating and substrate.