• Title/Summary/Keyword: MoSi$_2$ 분말

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Synthesis of $SiC/MoSi_2$ Composites Using Polymeric Precursors (무기고분자를 이용한 $SiC/MoSi_2$ 혼합상의 합성)

  • Kim, Dong-Pyo;Lee, Jae-Do
    • Korean Journal of Materials Research
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    • v.6 no.5
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    • pp.515-523
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    • 1996
  • 세라믹 전구체로서 PCS와 PMS 두 종류의 실린콘 고분자를 합성하여 7, 15, 33 wt.%의 Mo분말, Mo(CO)6 금속화합물과 혼합한 뒤 130$0^{\circ}C$이상 가열하면 탄화물과 규화물의 다양한 세라믹복합재로 전이되었다. 특히 PMS용액에 7, 15 wt.% Mo분말을 분산하여 초음파 처리하면 열분해 수율이 60%까지 개선되고 전도성 소재인 SiC/MoSi2 복합조성의 세라믹스가 합성되었다. 그러나 풍부한 유기 반응기를 가진 PCS와 카보닐기가 탄소공급원으로 작용하는 Mo(CO)6를 반응물로 사용하였을 때는 SiC와 Mo2C와 같은 탄화물과 미향의 MoSi2 그리고 미확인상을 포함한 세라믹 복합상들이 얻어졌다.

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Research Trends of the Mo-Si-B Alloys as Next Generation Ultra-high-temperature Alloys (차세대 초고온 합금인 Mo-Si-B 합금의 연구 동향)

  • Choi, Won June;Park, Chun Woong;Park, Jung Hyo;Kim, Young Do;Byun, Jong Min
    • Journal of Powder Materials
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    • v.26 no.2
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    • pp.156-165
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    • 2019
  • Over the last decade, the next generation's ultra-high-temperature materials as an alternative to Nickel-based superalloys have been highlighted. Ultra-high-temperature materials based on refractory metals are one of several potential candidates. In particular, molybdenum alloys with small amounts of silicon and boron (Mo-Si-B alloys) have superior properties at high temperature. However, research related to Mo-Si-B alloys were mainly conducted by several developed countries but garnered little interest in Korea. Therefore, in this review paper, we introduce the development history of Mo-Si-B alloys briefly and discuss the properties, particularly the mechanical and oxidation properties of Mo-Si-B alloys. We also introduce the latest research trends of Mo-Si-B alloys based on the research paper. Finally, for domestic research related to this field, we explain why Mo-Si-B alloys should be developed and suggest the potential directions for Mo-Si-B alloys research.

Fabrication of Porous MoSi2 material for Heating Element through Self-propagating High Temperature Synthesis Process (연소합성법에 의한 발열성 다공질 MoSi2계 재료의 제조)

  • Song, In-Hyuck;Yun, Jung-Yeul;Kim, Hai-Doo
    • Journal of the Korean Ceramic Society
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    • v.41 no.1
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    • pp.62-68
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    • 2004
  • In this study, SHS process has been employed to fabricate porous $MoSi_2$ material with electric-resistive heating capability through the control of pore size. The preform for SHS reaction was consisted of molybdenum powder with different sizes and silicon powder with different contained quantity. The size of the $MoSi_2$ particles thus formed was determined by the generated heat of combustion, not by the size of molybdenum powder. However, the pore size of $MoSi_2$ composite was proportional to the particle size of molybdenum powder. that is the coarser the molybdenum powder used, the larget the formed pore size. Based on these results, the porous $MoSi_2$ composite could be fabricated with a desired pore size. By orienting the porous molybdenum disilicide-based material in the form of pore size gradient, porous materials used for filters with improved dirt-holding capacity can be manufactured.

Fabrication of $MoSi_2$-TiC Composite Powders by Mechanical Alloying (기계적 압금화에 의한 $MoSi_2$-TiC 복합분말의 제조)

  • 윤종열
    • Journal of Powder Materials
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    • v.6 no.2
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    • pp.178-185
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    • 1999
  • MoSi$_2$-TiC composite powders were fabricated by in-situ reaction through mechanical alloying. Also the monolithic MoSi$_2$ as well as TiC were synthesiced by mechanical alloying for comparison. An abrupt increase of vial surface temperature was detected due to a sudden reaction between elemental powders during milling. The reaction time for synthesis of composite powders decreased with increasing the content of (Ti+C) powder. It was found that a significant decrease of Ti grain size was observed with increasing the milling time. And the synthesis reaction of MoSi$_2$-TiC composite powders were largely dependent on the reaction between Ti and C powders.

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