• Journal of Powder Materials
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• 제15권4호
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• pp.279-284
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• 2008

Dense nanostructured $NbSi_2$ was synthesized by high-frequency induction-heated combustion synthesis (HFIHCS) method within 1 minute in one step from mechanically activated Nb and Si powders. Highly dense $NbSi_2$ with relative density of up to 99% was simultaneously synthesized and consolidated under the combined effects of an induced current and mechanical pressure of 60 MPa. The average grain size and mechanical properties (hardness and fracture toughness) of the compound were investigated.

• Journal of Powder Materials
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• 제12권1호
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• pp.17-23
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• 2005

Dense $WSi_2$-20vol.%SiC composite was synthesized by high-frequency induction-heated combustion synthesis(HFIHCS) method within 2 minutes in one step from elemental powder mixture of W, Si and C. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. Highly dense $WSi_2$-20vol.%SiC with relative density of up to 97% was produced under simultaneous application of 60MPa pressure and the induced current. The average grain size of $WSi_2$ was about $5.2{\mu}m$. The hardness and fracture toughness values obtained were 1700kg/$mm^2$ and $4.4MPa{\cdot}m^{1/2}$, respectively.

• Journal of Powder Materials
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• 제16권1호
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• pp.16-21
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• 2009

Nanostructured $ReSi_{1.75}$ was synthesized to have high density via rapid and cost effective process named as high-frequency induction heated combustion synthesis(HFIHCS) method. For the process, mechanically activated Re-Si powder was used, which had been prepared by mechanical ball milling of Re and Si powders with mixing ratio of 1:1.75. Both combustion synthesis and densification were accomplished simultaneously by applying electric current and mechanical pressure of 80 MPa during the process. The average grain size, hardness, and fracture toughness of the compound were 210 nm, 1085 $kg/mm^2$ and 4 $MPa{\cdot}m^{1/2}$, respectively. The experimental results show that HFIHCS is a promising process for synthesis of nanostructured $ReSi_{1.75}$ which has a potential for both high temperature and thermo-electric applications.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2005년도 춘계학술강연 및 발표대회강연 및 발표논문 초록집
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• pp.42-43
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2003년도 춘계학술강연 및 발표대회
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• pp.43-44
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• 2003

• Journal of Powder Materials
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• 제10권2호
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• pp.108-117
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• 2003

WC and dense WC-10 vol%Co materials with grain size of~1${\mu}m$ were synthesized by high-frequency induction heated combustion synthesis (HFIHCS) method in one step from elemental powders of W, C and Co within several minutes. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. In the absence of cobalt additive, WC can be formed, but its relative density was low (about 73%) under simultaneous application of a 60 MPa pressure and the induced current. However, in the presence of 10 vol.%Co, the relative density increased to 99% under the same experimental condition. The percentages of the total shrinkage occurring before and during the synthesis reaction of WC-10 vol.%Co were 5% and 51%, respectively. The fracture toughness and hardness values of WC-10 vol.%Co were 10 MPa . m$^{1/2}$ and 1840 kg/$mm^2$, respectively.

• Journal of Powder Materials
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• 제16권2호
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• pp.91-97
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• 2009

Nanopowders of $Co_3O_4$ and FeAl were fabricated by high energy ball milling. Dense 4.25 $Co_{0.53}Fe_{0.47}-Al_2O_3$ composite was simultaneously synthesized and consolidated by high frequency induction heated combustion method within 2 min from mechanically activated powders. Consolidation was accomplished under the combined effects of a induced current and mechanical pressure of 80 MPa.

• Proceedings of the Korean Ceranic Society Conference
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• 한국세라믹학회 2003년도 춘계총회 및 연구발표회 초록집
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• pp.29.1-29
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2005년도 추계학술강연 및 발표대회강연 및 발표논문 초록집
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• pp.63-63
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• 2005

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 한국분말야금학회 2003년도 international symposium on advanced powder metallurgy
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• pp.41-42
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• 2003

Using a developed high-frequency induction heated combustion method. the simultaneous synthesis and densification of WC-xvol.%Co($0{\leq}x{\leq}20$) hard materials was accomplished using elemental powders of W, C and Co. A complete synthesis and densification of the materials was achieved in one step within a duration of 1min. The final relative densities of the composite were over 98.5% for all cases, under the applied pressure of 60 MPa and the induced current. The hardness of the composites decreases and the fracture toughness increases with increasing cobalt content. As the carbon to tungsten ration increases, the hardness increase, but the fracture toughness decreases. The maximum values for the fracture toughness and hardness are 15.1 $MPa{\cdot}m^{1/2}$(at 20vol.%Co, W:C=1:1), and 1928 $kg/mm^{2}$(at 5vol.%Co, W:C=1:1.3), respectively. Therefore we concluded that the HFIHCS method. which can produce WC-xvol.%Co within 1 minute in one step is superior to conventional ones.