• The Korean Journal of Ceramics
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• 제6권3호
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• pp.250-257
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• 2000

The feasibility of synthesizing SiC-AlN solid solution by field-activated combustion synthesis was demonstrated. At lower fields of 8-16.5V/cm, composites of AlN-rich and SiC-rich phases were synthesized, but at fields of 25-30 V/cm, the product was a 2H structure solid solution. Combustion synthesis of the solid solution by nitridation of aluminum with silicon carbide under a nitrogen gas pressure of 4-8 MPa was also investigated. The maximum combustion temperature and wave propagation velocity were found to be influenced by the electric field in the field-activated combustion synthesis, and by the green density and nitrogen pressure in the combustion nitridation. In both cases the formation of solid solutions is complete within seconds, considerably faster than in conventional methods which require hours.

• 한국재료학회지
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• 제9권7호
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• pp.680-687
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• 1999

Fe-Al계 금속간화합물이 FACS (Field-Activated Combustion Synthesis) 법에 의해 제조되었다. 이 계의 반응에 있어서 조성 (Fe:Al=3 : 1,2 : 1, 1 : 1.1 : 2, 1 : 3) , 성형압력 (150, 250, 350MPa), 저항 등이 조사되었는데. Al의 몰비, 성형압력, 전기장의 세가가 증가함에 따라서 연소온도와 연소속도는 증가하였다. 또한 이 계에 있어서 전류적용방식에 따른 반응에 대한 영향이 조사되었다. 전기장이 적용되지 않는 경우, 반응이 일어나기 위해서는 예열이 필요하였고, 예열을 하였을 경우라도 그 반응은 불안정연소파를 나타내어 완전한 반응이 이루어지지 않았다. 생성물은 X-ray, SEM, EDXS를 사용하여 그 구조와 조성을 관찰하였다

• The Korean Journal of Ceramics
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• 제5권2호
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• pp.148-154
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• 1999

A method to simultaneously synthesize and consolidate $Ti_5Si_4 \;and\; Ti_5Si_3$-20 vol%Nb composite from powders of Ti, Si and Nb was investigated. Combustion synthesis was carried out under the combined effect of an electric field and mechanical pressure. Highly dense $Ti_5Si_4 \;and\; Ti_5Si_3$-20 vol% Nb with relative densities up to 98% was produced from powders of Ti, Si and Nb under the application of 60 MPa pressure and 3000A current on the reactant.

• 소성∙가공
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• 제8권3호
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• pp.253-253
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• 1999

Dense WC-10 vol.%Co composite was simultaneously synthesized with field-activated and pressure-assisted combustion synthesis (FAPACS) within several minutes in one step from elemental powders of W, C and Co. Combustion synthesis was carried out under the combined effect of an electric field and mechanical pressure. Under the application of 60MPa pressure and 3000A current on the reactants, the relative density of WC-10 vol.%Co composite was 98.4%. The fracture toughness and hardness of WC-10 vol.%Co were 8.6 MPa·$m^{1/2}$ and 1900 kg/mm², respectively.

• The Korean Journal of Ceramics
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• 제6권2호
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• pp.172-176
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• 2000

Solid solutions of Ti$_{0.5}$Zr$_{0.5}$B$_2$were successfully synthesized and densified simultaneously from elemental reactants by the use of a field-activated, pressure-assisted synthesis method. The method involves the application of an electric current and mechanical pressure across reactant compacts to achieve combustion synthesis. Dense solid solutions with relative densities of up to 99% were produced and characterized by XRD, SEM, and EPMA methods. With a maximum measured temperature of 145$0^{\circ}C$ under a load of 86 MPa for 30 min, the desired dense solid solution wad synthesized.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2000년도 춘계총회,특별강연,심포지움,연구발표회
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• pp.97.2-97.2
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• 2000

• 한국재료학회:학술대회논문집
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• 한국재료학회 2002년도 춘계 학술발표강연 및 논문개요집
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• pp.118-118
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• 2002

• 열처리공학회지
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• 제14권1호
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• pp.1-7
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• 2001

A method to simultaneously synthesize and consolidate the silicide $NiSi_2$ and the composite $NiSi_2$-20vol.%Nb from powders of Ni, Si, and Nb was investigated. Combustion synthesis was carried out under the combined effect of an electric field and mechanical pressure. The final density of the products increased nearly linearly with the applied pressure. Highly dense $NiSi_2$ and $NiSi_2$-20vol.%Nb with relative densities of up to 97% were produced under the simultaneous application of a 60MPa pressure and a 3000A current on the reactant powders. The respective Vickers microhardness values for these materials were 6.0 and 5.8 GPa. From indentation crack measurements, the fracture toughness values for $NiSi_2$ and $NiSi_2$-20vol.%Nb were calculated to be 3.3 and 4.7 $MPa{\cdot}m^{1/2}$, respectively.

• 한국분말재료학회지
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• 제8권4호
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• pp.231-238
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• 2001

We combined Field-Activated Combustion Synthesis(FACS) with mechanical pressure to produce dense WC-20 vol.%Co composite in one step. The hardness, the fracture toughness and the relative density of the dense WC-20 vol.%Co were investigated. Under the application of 60 MPa pressure and 3000A current on the reactants, the relative density of WC-20 vol.%Co composite was 99.4%. The fracture toughness and hardness were $9.4 MPa.m^{1/2}$ and $1672kg\textrm{mm}^2$ respectively. The fracture toughness and hardness of WC-20 vol.%Co composite produced by FAPACS were lower than that of nanostructured composite, but similar to commercial ones. Therefore we concluded that the FAPACS method which can produce WC-20 vol.%Co within several minutes in one step is superior to conventional ones.

• 한국재료학회지
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• 제6권7호
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• pp.709-715
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• 1996

${Ti}_{5}{Si}_{3}$와 ${Ti}_{5}{Si}_{3}-{ZrO}_{2}$ 복합재료의 연소합성에 미치는 전기장의 영향에 관하여 연구하였다. 45mole% 이상 첨가한 ${Ti}_{5}{Si}_{3}-{ZrO}_{2}$ 복합재료는 전기장하에서만 연소합성할 수 있었다. ${Ti}_{5}{Si}_{3}$-45mole% ${ZrO}_{2}$와 Ti5Si3-60mole% ${ZrO}_{2}$ 복합재료는 전기장을 가하지 않은 상태에서는 불안정한 연소파가 전파되었지만 반응은 완전히 일어나지 않았다 즉, 불안정한 연소파는 시편의 중앙 부근까지 전파 된 후 멈추었다. ${Ti}_{5}{Si}_{3}$-ZrO2 복합재료의 연소파 속도는 시편에 가해준 전기장에 의해 약간 증가하였다.