• 제목/요약/키워드: SHS

검색결과 370건 처리시간 0.027초

SHS 화학로에 의한 (Ti.W)C 복탄화물의 합성 및 기계적 특성에 관한 연구 (A Study on Synthesis and Mechanical Properties of (Ti.W)C Complex Carbide by SHS Chemical Furnace)

  • 이형복;오유근;이풍헌;장동환
    • 한국세라믹학회지
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    • 제33권4호
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    • pp.418-424
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    • 1996
  • (Ti.W)C complex carbide was synthesized by self-propagating high temperature synthesis (SHS) chemical furnace. Attempt to find the optimal condition for synthesis of (Ti.W)C the effects of molar ratio of Ti:W:C on the synthesized powders and mechanical properties were investigated, Optimum molar ratio of these synthe-sized powder was Ti:W:C=0.7:0.2:1.0 The bulk density M,O.R Hardness Fracture toughness of (Ti.W)C complex carbide sintered at 200$0^{\circ}C$ for 60 min by hot-pressing under the pressure of 20 MPa were 7.6g/cm3, 475 MPa, 17,.7 GPa respectively.

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알루미늄 주물 위 용탕열을 이용한 N-Al계 금속간화합물의 연소합성 코팅 (Ni-Al Based Intermetallics Coating Through SHS using the Heat of Molten Aluminum)

  • 이한영;조용재
    • 한국주조공학회지
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    • 제31권2호
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    • pp.83-86
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    • 2011
  • Ni-Al based intermetallic compounds of self-propagating high-temperature synthesis (SHS) by the heat of molten aluminum and been coated on the aluminum casting alloy. The effects of the pouring temperature in casting and the thickness of casting substrate on SHS of the coating layer have been investigated. The experimental result showed that the reaction of the coating layer was activated with increasing the pouring temperature in casting and the thickness of casting substrate. However, the aluminum substrate was re-melted by the heat of formation for intermetallic compounds. Then, it was considered that some mechanical or thermal treatments for elemental powder mixtures were required to control the heat of formation for intermetallic compounds in advance.

Numerical investigation of continuous hollow steel beam strengthened using CFRP

  • Keykha, Amir Hamzeh
    • Structural Engineering and Mechanics
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    • 제66권4호
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    • pp.439-444
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    • 2018
  • This paper presents a numerical study on the behavior of continuous hollow steel beam strengthened using carbon fiber reinforced polymers (CFRP). Most previous studies on the CFRP strengthening of steel beams have been carried out on the steel beams with simple boundary conditions. No independent study, to the researcher's knowledge, has studied on the CFRP strengthening of square hollow section (SHS) continuous steel beam. However, this study explored the effect of the use of adhesively bonded CFRP flexible sheets on the behavior of the continuous SHS steel beams. Finite Element Method (FEM) has been employed for modeling. Eleven specimens, ten of which were strengthened using CFRP sheets, were analyzed under different coverage length, the number of layers, and the location of CFRP composite. ANSYS software was used to analyze the SHS steel beams. The results showed that the coverage length, the number of layers, and the location of CFRP composite are effective in increasing the ultimate load capacity of the continuous SHS steel beams. Application of CFRP composite also caused the ductility increase some strengthened specimens.

Streptomyces floridae SHS-1372가 생산하는 항암항생물질 HS-1의 특성 (Characteristics of Antitumor Antibiotics HS-1 from a Stveptomyces JIoridiae SHS-1372)

  • 하상철;홍순덕
    • 한국미생물·생명공학회지
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    • 제22권2호
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    • pp.169-174
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    • 1994
  • Antitumor antibiotic HS-1 was purified from the culture broth of a streptomyces floridae SHS-1372 which had been isolated from soil, by solvent extraction, silica gel column chromatography and gel filtration. It was confirmed that HS-1 was active against gram positive bacteria and cancer cells(K562, P388, MCF-7, HT-29). Through the analysis of UV spectrum, melting point, IR spectrum, FAB-MS, $_{1}$H-NMR, $_{13}$C-NMR, 2D-NMR spectra, HS-1 could be identified sa the actinomycin X$_{2}$ antibiotics containing actinocine chromophore and peptides consisted of threonine, proline, methylvaline, sarcosine, D-valine and 4-ketoproline.

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Peculiarities of SHS and Solid State Synthesis of ReBa2Cu3O7-x Materials

  • Soh, Deawha;Natalya, Korobova
    • 한국전기전자재료학회논문지
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    • 제15권3호
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    • pp.275-280
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    • 2002
  • The peculiarities of using Self-propagating High-temperature Synthesis (SHS) and solid-stave chase synthesis for production of high temperature superconductor materials were discussed. Oxide superconductors with general formula of $ReBa_2Cu_3O_{7-x}$ (Re=Y, Sm) haute been made by using barium oxide initial powder instead of traditional barium carbonate. Phenomena observed during the grinding of the reactants mixture are presented. Mechano-chemical activation - as a pre-treatment of the reactants mixture - strongly influences the kinetic parameters, the reaction mechanism, and the composition and structure of the final product.

SHS of Oxide Systems Based on MCR of Quartz Modified by Organometallic Compounds

  • Soh, Dea-Wha;Tlek, Ketegenov;Z.A., Mansurov
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.666-669
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    • 2002
  • The differences of the effects of mechanical substance pre-activation in the mills with divers force effect schemes on the self-propagating high temperature synthesis (SHS) of the $SiO_2$ + 37.5% Al system were investigated. The power saturation of activated material state are estimated referring on the variations of dilatometry curve paths. The effects of activation time on the temperature of sample self-ignited in the furnace, combustion temperature and completeness of the quartz reaction with aluminium were determined. The enhancing effects of organic modifiers of quartz particle surfaces on the further SHS synthesis development were shown.

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SHS법에 의한 $TiB_{2}/Cu$계 경사기능재료의 제조 (Synthesis of $TiB_{2}/Cu$ FGM by SHS process)

  • 박현철;연석주
    • 한국결정성장학회지
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    • 제5권4호
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    • pp.386-393
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    • 1995
  • SHS법에 의한 경사기능재료를 제조하는 방법을 조사하여 그 방법에 따라 $TiB_2/Cu$ 경사기능재료를 제조하고자 한다. 이때 원료분말을 구리에 침적하면서 조성의 구배를 주고, 가압 성형한 후 합성을 하기 위한 반응조에 넣었다. 이 시료를 점화시켜 정수압 하에서 합성과 동시에 가압하였다. 이렇게 제조된 $TiB_2/Cu$ 경사기능재료의 결정상, 미세주고 등을 관찰하여 조성의 경사를 확인할 수 있었다.

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Synthesis of $Bi_{2+x}Sr_2Ca_{n-1}Cu_{n}O_{4+2n+d}$ compounds by SHS

  • Soh, Deawha;Cho,Yongioon;Korobova, N.;Isaikina, O.
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집
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    • pp.94-97
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    • 2002
  • BSCCO (2223) compound which has the highest temperature of transition to the superconducting state in the homologous series considered is synthesized by SHS. The method exploits self-sustaining solid-flame combustion reactions which develop very high internal material temperatures over short periods. This report introduces the SHS method and its advantages and discusses its application in the synthesis of superconducting materials.

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SHS법에 의한 $Al_2O_3-SiC$ 복합분말의 합성 (Preparation of $Al_2O_3-SiC$ Composite Powder by SHS Method)

  • 이형민;이홍림;이형직
    • 한국세라믹학회지
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    • 제32권1호
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    • pp.11-16
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    • 1995
  • High reaction heat evolved from the oxidation of Al was used to synthesize SiC, which might be difficult to be formed by SHS. Al2O3-SiC composite powder was easily manufactured using KNO3 as an ignition and reaction catalyst. Unreacted Si and C were observed after reaction dependent upon the composition of starting powders, reaction atmosphere and relative densities of compacted bodies. The unreacted carbon could be removed by calcining at $600^{\circ}C$ and the remaining Si could be removed by dissolving in NaOH solution. The final powder particles were smaller than 1${\mu}{\textrm}{m}$ in size.

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Properties of Hot Pressed Alumina-Titanium Diboride Particulate Composites

  • Park, Dong-Soo;Han, Byung-Dong
    • The Korean Journal of Ceramics
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    • 제4권3호
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    • pp.227-230
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    • 1998
  • Alumina($Al_2O_3$)-Titanium Diboride($TiB_2) particulate composites were fabricated by hot pressing of the powder mixture that was prepared from Self-propagating High Temperature Synthesis (SHS) product and commercial powders. Their propeties were examined in order to find feasibility of using SHS for making the high performance ceramic composite. $TiB_2 particles obtained by grinding the SHS product were finer than the commercial powders. Hot pressed sample containing the SHS products exhibited higher strength than the one prepared from the commercial powders.

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