• 제목/요약/키워드: Mechanochemistry

검색결과 21건 처리시간 0.047초

Cold and Detonation Spraying of $TiB_2-Cu$ Nanocomposites

  • Lomovsky, O.I.;Dudina, D.V.;Korchagin, M.A.;Kosarev, V.F.;Klinkov, S.V.;Ulianitsky, V.Yu.;Kim, J.S.;Kwon, Y.S.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.680.2-680.2
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    • 2006
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TiB2-Cu Interpenetrating Phase Composites Produced by Spark-plasma Sintering

  • Kwon, Young-Soon;V. Dudina, Dina;I. Lomovsky, Oleg;A. Korchagin, Michail;Kim, Ji-Soon
    • 한국분말재료학회지
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    • 제10권3호
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    • pp.168-171
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    • 2003
  • Interpenetrating phase composites of $TiB_2$-Cu system were produced via Spark-Plasma Sintering (SPS) oi nanocomposite powders. Under simultaneous action of pressure, temperature and electric current titanium diboride nanoparticles distributed in copper matrix move, agglomerate and form a fine-grained skeleton. Increasing SPS-temperature and he]ding time promote densification due to local melting of copper matrix When copper melting is avoided the compacts contain 17-20% porosity but titanium diboride skeleton is still formed representing the feature of SPS . High degree of densification and formation of titanium diboride network result in increased hardness of high-temperature SPS-compacts.

Shock-wave Synthesis of Titanium Diboride in Copper Matrix and Compaction of $TiB_2$-Cu Nanocomposites

  • Lomovsky, O.I.;Mali, V.I.;Dudina, D.V.;Korchagin, M.A.;Kwon, D.H.;Kim, J.S.;Kwon, Y.S.
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part2
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    • pp.1084-1085
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    • 2006
  • We studied formation of nanostructured $TiB_2$-Cu composites under shock wave conditions. We investigated the influence of preliminary mechanical activation (MA) of Ti-B-Cu powder mixtures on the peculiarities of the reaction between Ti and B under shock wave. In the MA-ed mixture the reaction proceeded completely while in the non-activated mixture the reagents remained along with the product . titanium diboride. The size of titanium diboride particles in the central part of the compact was 100-300 nm.

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Mechanochemistry: from Mechanical Degradation to Novel Materials Properties

  • Sepelak, V.;Becker, K.D.
    • 한국세라믹학회지
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    • 제49권1호
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    • pp.19-28
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    • 2012
  • High-energy mechanical action applied to solid leads to destruction and diminution to the nanosize level. But on the other hand, it can induce structural changes at the nanoscale and at the atomic level which can result in novel materials properties. In this contribution, case studies will be presented concerned with the tailoring of magnetic properties of mechanically treated nanomaterials. Emphasis is placed on materials that have been synthesized by mechanochemical means and on an improved understanding of their nanomagnetism in general. The associated local structural changes of the iron containing magnetic materials discussed in the examples have been studied most suitably by $^{57}Fe$ Mossbauer nuclear probe spectroscopy whose results are supplemented by measurements of the magnetic properties of the mechanosynthesized nanomaterials.

고분자물질과 접촉한 자기조립단분자막 전극 물질의 기계화학 현상 분광학적 연구 (Mechanochemistry on Self-Assembled Monolayer(SAM) /Electrodes after Contacting with Polymeric Stamp)

  • 윤창석
    • 한국표면공학회지
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    • 제53권5호
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    • pp.265-270
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    • 2020
  • We investigated mechanochemical radical, which is concomitant with chemical lift-off lithography(CLL), on the self-assembled monolayer(SAM)/electrodes and a polydimethylsiloxane(PDMS) using a colorimetric and a spectroscopic method. The 11-mercaptoundecanol(MUO)/Au or the 11-hydroxyundecylphosphonic acid (HUPA)/ITO were contacted with bare or activated PDMS. After contact, the each of SAM/substrates and the PDMS were immersed in a 2,2 Diphenyl-1-picrylhydrazyl(DPPH) radical scavenger. The color of the DPPH exposed to the PDMS was changed from purple to yellow and the absorbance decreased definitely at 515 nm wavelength. The SAM/substrates, however, have caused small changes in spectroscopic property, indicating no existence of radical species. We concluded that mechanochemical radicals were formed by homolytic cleavage of PDMS molecules upon external force and hardly transferred on the SAM/substrates.