• Title/Summary/Keyword: 플라즈마 용사 코팅

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Effect of Heat Treatment of Fatigue Crack Growth of Plasma-Sprayed Coating Steels (플라즈마 용사코팅강재의 피로균열성장에 미치는 감화열처리의 영향)

  • Kim, G.S.;Hyun, C.H.;Kim, Y.S.
    • Journal of Power System Engineering
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    • v.7 no.4
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    • pp.55-60
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    • 2003
  • This paper is to investigate the fatigue crack growth of plasma-sprayed coating steels according to heat treatments. The experimental materials are carbon steels(substrate: S45C) with plasma-sprayed coating layers of Ni-4.5%Al and $TiO_2$. The fatigue test is conducted on compact tension specimen by a servo-hydraulic fatigue testing machine. The specimens are heat-treated at $400^{\circ}C\;and\;800^{\circ}C$, respectively. Loading condition is a constant amplitude sinusoidal wave with a frequency of 10Hz and a load ratio of 0.1. The fatigue crack growth length is automatically measured by a compliance method. In the case of non-heat treated specimens, the fatigue crack growth rates of both substrate and coating specimen are almost same. The crack growth rates of substrates and coating steels by heat treatment are larger than those of the non-heat treated one, because the ductile property increase by heat treatment. In ${\Delta}K<18MPa{\cdot}m^{1/2}$, the crack growth rates of the heat-treated specimens are slightly taster than non-heat treated one. But the both heated and non-heated one are almost same in ${\Delta}K>18MPa{\cdot}m^{1/2}$.

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Fabrication and characteristics of suspension-plasma-sprayed yttrium oxide coatings (서스펜션 플라즈마 스프레이 코팅법을 이용한 이트리아 코팅막 제조와 특성)

  • Kim, Min Suk;So, Sung Min;Kim, Hyung Soon;Park, Seong Hwan;Ham, Young Jae;Jeon, Min Seok;Kim, Kyoung Hun
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.29 no.6
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    • pp.359-364
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    • 2019
  • The suspension plasma spraying is a modification of conventional plasma spray techniques that has been developed to overcome the challenge of using fine particles in plasma spray processes. In this study, microstructure developments and mechanical property of yttrium oxide (Y2O3) coatings prepared by the suspension plasma spray coating technique have been investigated to determine the effect of processing parameters including plasma gun current and total gas flow. The results showed that a highly dense Y2O3 coating having low porosity of 0.2 vol% without any lamellar structures can be achieved at the optimum condition of gun current 200 A and total gas flow 220 L/min.

Study of the thermal shock resistance of multi-coating for C/C composite by plasma spray coating (플라즈마 용사법에 의해 다층코팅된 탄소탄소복합재료의 열충격 저항성 연구)

  • Lee, Gu-Hyeon;Jeong, Seong-Il;Byeon, Eung-Seon;Nam, Gi-Seok
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2013.05a
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    • pp.106-106
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    • 2013
  • C/C Composite는 비교적 낮은 온도에서 산화되어 고유의 특성을 쉽게 잃어버리게 된다. 본 연구에서는 Plasma Spray 코팅방법을 사용하여 다층 코팅층을 형성 시킨 후 $1600^{\circ}C$의 온도에서 열충격 저항성을 평가하였다.

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Microwave Absorbing Characteristics of Silicon carbide-ferrite surface Films Produced by Plasma-spraying(I) (플라즈마 용사방식에 의해 형성된 탄화규소-페라이트 표면층의 마이크로파 흡수특성(I))

  • Shin, Dong-Chan;Son, Hyon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.17 no.6
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    • pp.580-588
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    • 1992
  • Plasma-spraying was conducted to produced the microwave absorbing surface films on the alumi-num-alloy used for the fuselage to protect the aircraft against the RADAR detction. The surface films were produced by plasma-splaying the mecharucally mixed composite powders of the silicon carblde and Ni-Zn ferrite. This M /W absorbers were designed experimentally and fabricated trialty, as a result of which the rolative frequency bandwidth of 7.6 to 8.4% were obtained under the tolerance limits of the re-flection coefficients lower than -6dB(absorption ratio 75%), and the maximum absorption thickness becomes 0.5 to 0.5.imm, which Is much thinner than that of the conventional ones.

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