• 제목/요약/키워드: Plasma spraying

검색결과 152건 처리시간 0.038초

고기능 $TiO_2$ 광촉매 용사피막의 내마모성 거동에 관한 연구 (The Wear Resistance Behavior of Functional Thermal sprayed $TiO_2$ Photocatalytic Coatings on Bio-degradable Plastic)

  • 방희선;방한서;;;김영표;윤덕영
    • 대한용접접합학회:학술대회논문집
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    • 대한용접접합학회 2004년도 춘계 학술발표대회 개요집
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    • pp.314-315
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    • 2004
  • As environmental issue threatens to be aggravated, applications of bio-degradable plastic (Polybutylene Succinate:PBS) tend to be increased. However, improvement of mechanical characteristics of PBS is indispensable for further widespread actual applications. Therefore, in order to produce further functional P8S with improved mechanical characteristics, TiO$_2$ coatings on PBS substrate were prepared under various spraying conditions using plasma and HVOF spraying techniques. The effects of thermal spraying methods and spraying parameters on coating properties could be confirmed. Moreover, wear behavior for TiO$_2$ coatings on PBS substrate has been also reviewed and characterized.

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Ti-based Quasicrystal Layers Produced by Plasma Thermal Spraying

  • Takasaki, Akito;Uematsu, Susumu;Kelton, K.F.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.51-52
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    • 2006
  • [ $Ti_{45}Zr_{38}Ni_{17}$ ] powders were thermally sprayed onto mild steel substrates in air and under a reduced pressure of argon. Several oxides were formed after thermally-spraying the mechanically-alloyed powders in air. After spraying in a reduced pressure of argon, the coating layers obtained from the gently mixed powders consisted of the elemental metals, but an amorphous phase primarily appeared in the thermally-sprayed mechanically-alloyed powders, which transformed into the icosahedral quasicrystal phase and a minor $Ti_2Ni-type$ crystal phase after annealing at 828 K. The Vickers hardness and the contact angle with pure water for the quasicrystal layers were about 7 GPa and $92^{\circ}$ respectively.

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NEW FRONTIERS IN THERMAL PLASMAS FROM SPACE TO NANOMATERIALS

  • Boulos, Maher I.
    • Nuclear Engineering and Technology
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    • 제44권1호
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    • pp.1-8
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    • 2012
  • Thermal plasma technology has been at the center of major developments over the past century. It has found numerous applications ranging from aerospace materials testing to nanopowder synthesis and processing. In the present review highlights of principal breakthroughs in this field are presented with emphasis on an analysis of the basic phenomena involved, and the potential of the technology for industrial scale applications.

플라즈마 스프레이 (LaSr)(CrCo)O3 코팅된 STS-430 합금의 고온 산화 거동 및 전기적 특성 (Oxidation and Electrical Properties of (LaSr)(CrCo)3Coated STS-430 Steel by Plasma Spraying)

  • 이충환;임경태;백경호
    • 한국분말재료학회지
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    • 제16권3호
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    • pp.185-190
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    • 2009
  • Fe-Cr steels are the most promising candidate for interconnect in solid oxide fuel cells. In this study, an effective, dense and well adherent (LaSr)(CrCo)$O_3$ [LSCC] coating layer was produced onto 430 stainless steel (STS-430) by atmospheric plasma spraying and the oxidation behavior as well as electrical properties of the LSCC coated STS-430 were investigated. A significant oxidation of pristine STS-430 occurred at $800^{\circ}C$ in air environment, leading to the formation of $Cr_2O_3$ and $FeCr_2O_4$ scale layer up to ${\sim}7{\mu}m$ after 1200h, and consequently increased an area specific resistance of $330\;m{\Omega}{\cdot}cm^2$. Although the plasma sprayed LSCC coating contained the characteristic pore network, the coated samples presented apparent advantages in reducing oxidation growth of STS-430, resulting a decrease in oxide scale thickness of ${\sim}1{\mu}m$ at $800^{\circ}C$ after 1200h. The area specific resistance of the LSCC coated STS-430 was much reduced to ${\sim}7\;m{\Omega}{\cdot}cm^2$ after exposure at $800^{\circ}C$ for 1200h, compared to that of the pristine STS-403.

분말송급장치의 개조에 의한 미세$5\mu\textrm{m}$ $Al_2O_3$분말의 송급 특성개선 및 플라즈마 용사조건에 따른 코팅층의 특성분석 (Improvement of Powder Feeding Characteristics of Fine$5\mu\textrm{m}$ $Al_2O_3$ Powder by Modification of the Powder Feeding Systems and Characterization of the Coating Layer depending on Plasma Spraying Conditions)

  • 설동욱;김병희;정민석;임영우;서동수
    • Journal of Welding and Joining
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    • 제15권1호
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    • pp.116-124
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    • 1997
  • A scope of this study is to establish the optimum plasma spray conditions for fine ($5\mu\textrm{m}$) $Al_2O_3$ powder. However, the flowability of the $Al_2O_3$ powder is not so good because of irregular particle shape and fine particle size. Therefore, powder feeding system was modified by 1) change of powder feeding line material from polymer to copper 2) shorten the powder feeding tube length 3) heating the powder feeding system to $80^{\circ}C$4) vibrating the powder feeding line continuously, in order to feed the fine powder homogeneously. The homogeneous powder feeding conditions were obtained with the modified powder feeding system by controlling the powder carrier gas flow and the powder flow rate indicator. The best plasma spraying conditions for the fine $Al_2O_3$ powder were found out as 40kw gun power, 80 g/min. powder feed rate and 50 mm working distance after characterizing the microstructure, hardness and wear loss of the $Al_2O_3$ coating layer.

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하프늄카바이드 코팅을 통한 2종형상의 탄소/탄소복합재의 내삭마성 향상연구 (A Study on Improvement of the Ablation Resistance of Two Types of the Carbon/Carbon Composites by HfC Coating)

  • 강보람;김호석;오필용;최성만
    • Composites Research
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    • 제33권4호
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    • pp.205-212
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    • 2020
  • 본 연구에서는 기상화학반응공정을 이용하여 실리콘카바이드가 코팅된 2종형상의 탄소/탄소복합재 위에 진공플라즈마용사를이용하여 하프늄카바이드를 코팅하였다. 코팅 전/후 시편을 5.06 MW/㎡의 열유속에서 120초 동안 산화 및 삭마 실험을 진행하였다. 시험 전/후의 질량 변화량을 통해 질량삭마율을 계산하였고 캘리퍼스와 고속카메라를 이용하여 길이변화를 측정하여 길이삭마량을 계산하였다. 시편 단면의 FE-SEM 및 EDS 분석을 통해 산화 및 삭마거동을 관찰하였다. 플라즈마 풍동 시험결과 코팅된 시편이 무게감소 및 길이변화가 적어 내산화 및 내삭마성이 높은 것으로 판단되었다. 그러나 동일조건에서 시험한 반구형과 원통형의 산화 및 삭마정도는 상이하였고 원통형에서 더 높은 내산화 및 내삭마성을 가지는 것으로 평가되었다.