• 한국세라믹학회지
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• 제28권3호
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• pp.234-242
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• 1991

Ti-B system ceramics were prepared by the self-propagating high-temperature synthesis method from the mixture of metal titanium and boron powders The major crystalline phase as a function of boron content was TiB for mixtures containing 0.5 or 1.0mol B, and TiB2 for these containing over 1.3mol B. The combustion mode observed by a high-speed camera was steady-state. The Combustion velocity increased with increasing the boron content. Sintered TiB2 specimen showed the density of 97% of theoretical valve, Vicker's hardness of 2250kg/㎟ for 0.2kg load and three-point-flexure strength of 500MPa.

• 동굴
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• 제78호
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• pp.1-8
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• 2007

The combination of mechano-chemical activation (MCA)and Self-propagating High-temperature Synthesis (SHS) has widened the technical possibilities for both methods. For YBCO systems the investigation showed that a short-term MCA of initial powders before SHS leads to single-phase and ultra-fine products. A new technique for preparation ultra-fine high-temperature superconductors (HTS) of YBCO composition with a grain size d <1m is developed using combination of MCA and SHS. The specific feature of the technique is formation of the $YBa_2Cu_3O_7-$ crystalline lattice directly from an X-ray amorphous state arising as a result of mechanical activation of the original oxide mixture. The technique allows the stage of formation of any intermediate reaction products to be ruled out. X-ray and magnetic studies of ultra-fine high temperature superconductors are carried out. Dimension effects associated with the microstructure peculiarities are revealed. A considerable enhancement of inter-grain critical currents is found to take place in the ultra-fine samples.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1994년도 춘계학술대회강연 및 발표대회 강연및 발표논문 초록집
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• pp.5-5
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• 1994

• 시멘트
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• 통권119호
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• pp.7-13
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• 1990

• 한국세라믹학회지
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• 제33권10호
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• pp.1089-1094
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• 1996

In this study the formation mechanism of AlN synthesized by SHS(Self-propagating high-temperature Syn-thesis) was studied in order to obtain uniform AlN powder size and morphology. Based on the morphology of AlN synthesized and the calculation of the temperature of Al powder as a function AlN layer thickness the formation mechanism of AlN was proposed.

• 한국재료학회지
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• 제10권5호
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• pp.343-349
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• 2000

자전연소합성(SHS)법을 이용하여 탄소섬유와 티타늄, 지르코늄, 니오븀, 규소, 붕소, 중석, 몰리브덴의 분말로부터 여러 가지 섬유상 탄화물의 합성을 시도하였다. 티타늄과 지르코늄은 예열없이, 그 이외의 경우는 전기로 또는 화학로를 사용하여 예열하여 반응을일으킨 결과, TiC, ZrC, NbC, SiC, $B_4$C, WC,$ Mo_2$C 의 순수한 탄화물의 형성되었다. TiC, ZrC, NbC 및 $B_4$C 탄화물의 형상은 속의 빈 섬유상이었고, SiC는 보다 작은 입자와 미세 휘스커로 이루어진 섬유상을 하고 있었고 WC와 $Mo_2$C 는 비섬유상을 하고 있었다. 여러 가지 형상의 원인에 대하여 합리적 설명을 시도하였으며 정성적 메카니즘을 제안하였다.

• 한국세라믹학회지
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• 제31권3호
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• pp.265-274
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• 1994

Intermetallic Ti-Si system ceramics were synthesized from stochiometric mixtures of titanium and silicone powders in vacuum by Self-propagating High-temperature Synthesis(SHS). In each cases of Ti5Si3, Ti5Si4 and TiSi, and TiSi2 synthesis, 20wt% product dilution, direct ignition and SHS chemical furnace method were employed. The combustion modes, which were observed during the synthesis process by using the high speed camera, of Ti5Si3, Ti5Si4, TiSi, and TiSi2 exhibit spin, osciallatory, steady-state, and spin combustion, respectively. With increasing Ti/Si molar ratio an decrease of combustion velocities was found. From the results on the measurement of the flexural strength, the specimen hot pressed at 135$0^{\circ}C$ for 30 min using synthesized Ti5Si4 powders showed the highest flexural strength at 215 MPa.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2002년도 춘계학술발표대회 논문집
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• pp.155-158
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• 2002

Fabrication process of metal/intermetallic laminated composites by using self-propagating high temperature synthesis(SHS) reactions between Ni and Al elemental metal foils have been investigated. Al foils were sandwiched between Ni foils and heated in a vacuum hot press to the melting point of aluminium. SHS reaction kinetics was thermodynamically analyzed through the final volume fraction of the unreacted Al related with the initial thickness ratio of Ni:Al and diffusion bonding stage before SHS reaction. Thermal aging of laminated composites resulted in the formation of functionally gradient series of intermetallic phases. Microstructure showed that the main phases of intermetallics were NiAl and $Ni_3Al$ having higher strength at room and high temperatures. The volume fractions of intermetallic phases were measured as 82.4, 58.6, 38.4% in 1:1, 2:1, 4:1 initial thickness ratio of Ni:Al.

• 한국세라믹학회지
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• 제29권7호
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• pp.577-585
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• 1992

TiB2 and TiC were prepared from the mixture of metal titanium, boron and graphite powders in Argon atmosphere by Self-propagating High-temperature Synthesis method. The sintered properties of TiB2-TiC composite as a function of TiC content and sintering temperature were investigated in TiB2 matrix. The sintered properties were the most excellent at 10 wt% TiC content in TiB2-TiC composite. The relative density, M.O.R strength, hardness and fracture toughness of TiB2-10 wt% TiC composite sintered at 190$0^{\circ}C$ for 90 min by hot-pressing under the pressure of 30 MPa were 98.6%, 634 MPa, 2128.1 kg/$\textrm{mm}^2$ and 4.09 MN/m3/2, respectively.

• 자원리싸이클링
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• 제12권6호
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• pp.3-7
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• 2003

산화철의 제조에는 기존의 습식화학제조법과 건식화학제조법이 있는데, 모두 환경에 영향을 미치는 화학물질을 대량으로 사용하여 산화철을 제조하는 기술이다. 본 기술보고에서는 환경친화적 제조법으로 스크랩을 원료로 박테리아를 이용하여 산화철을 제조하는 생화학적 기술과 자전고온합성법을 이용하여 산화철을 제조하는 신개념의 산화철제조 기술을 소개하였다.