• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 1999년도 추계학술발표대회 논문집
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• pp.83-87
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• 1999

The fabrication process and thermal properties of 50~71vol% SiCp/Al metal matrix composites (MMCs) were investigated. The 50~71vol% SiCp/Al MMCs fabricated by pressure infiltration casting process showed that thermal conductivities were 118~170W/mK and coefficient of thermal expansion (CTE) were 9.5~$6.5{\times}10^{-6}/K$. Specially, the thermal conductivity and CTE of 71vol%SiCp/Al MMCs were 115~156W/mK and 6~$7{\times}10^{-6}/K$. respectively, which showed a improved themal properties than the conventional electronic packaging materials such as ceramics and metals.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 춘계학술발표대회 논문집
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• pp.139-142
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• 2000

The SiCp/AC8A composites were fabricated by the pressureless metal infiltration process successfully. The effect of additional Mg, which were mixed with SiC particles to promote interfacial wetting between the reinforcement and matrix alloy, and particle size on the mechanical properties was investigated. By increasing the additional Mg content the hardness of SiCp/AC8A composites was increased due to the hard reaction products, but the bending strength was decreased by the excess reaction of Mg and high porosity level when the additional Mg content is over 7%. The Hardness and bending strength was increased by decreasing the size of SiC particle.

• 한국주조공학회지
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• 제22권4호
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• pp.184-191
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• 2002

This study aims to investigate on the effects of alloying elements and heat treatment on the microstructures, wear and heat resistance of Al-Si-Cu-Mg-(Ni)/SiCp prepared by the duplex process developed in previous study, which consists of squeeze infiltration (1st process) and squeeze casting (2nd process). The hardness of composite increased with decrease in SiCp size and Ni addition in both the heat exposured composite and the as-cast one. And the heat and wear resisting properties was improved by the SiCp reinforcement and the Ni addition. The wear amount of Al/SiCp composite decreased with decreasing in the size of silicon carbide particle.

• 폴리머
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• 제39권1호
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• pp.169-173
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• 2015

3-Aminopropyltrimethoxysilane(1NS) 또는 N-[3-(trimethoxysilyl)propyl]ethylenediamine(2NS)으로 표면 기능화된 실리카에 1-butyl-4-methylpyridinium chloride(Cl)와 tributylmethylammonium chloride(Amm), benzyldimethyltetradecylammonium chloride(Ben), 1-butyl-1-methylpyrrolidinium chloride(Pyr)와 같은 이온성 액체를 이용하여 표면처리한 후 메탈로센 촉매를 담지하여 에틸렌 중합을 실시하였다. $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ 촉매와 $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$ 촉매의 Zr 함량은 아미노실란 화합물로만 표면 처리된 촉매보다 감소하였다. $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ 촉매의 중합 활성은 $SiO_2/1NS/(n-BuCp)_2ZrCl_2$ 촉매보다 증가하였다. 반면, $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$은 Zr 함량의 감소로 중합 활성은 $SiO_2/2NS/(n-BuCp)_2ZrCl_2$ 촉매에 비해 감소하였다.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 1994년도 추계학술대회강연 및 발표대회 강연및 발표논문 초록집
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• pp.27-27
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• 1994

• 대한화학회지
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• 제38권1호
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• pp.55-60
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• 1994

유기규소 중합반응에서 나타나는 중간체 $Cp_2TiSiHPh(1),\;[Cp_2Ti]_2[{\mu}-HSi(HPh)][{\mu}-H]$ (2) 그리고 $[Cp_2TiSiH_2Ph]_2$ (3)화합물들의 전자구조를 EHT방법으로 연구하였다. 1 화합물의 안정한 구조는 Cs로 변형된 형태이고 $SiH_2$의 회전에너지는 약 14 kcal/mol로 나타났다. 전자결핍분자인 2와 3 화합물의 결합특성을 전자구조를 통하여 규명하였다. 또한 Ti금속이 Si-H의 $\sigma$ 결합과 작용할 가능성을 설명하였다.

• 한국주조공학회지
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• 제13권6호
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• pp.524-531
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• 1993

Dispersion behaviors of SiC particles and microstructures in Al-2%Si/SiCp composite prepared by Rheo-compocasting were studied with change of fabrication conditions(slurry temperature, agitation time) and additions of Mg($0{\sim}3wt.%$). Also, the microhardness change of matrix, interface and total in composites were examined with additions of Mg($0{\sim}3wt.%$). The dispersion of particles in the composites became relatively homogeneous with increase of Mg additions, agitation time and decrease of slurry temperature. Rate of occupied area by particle in matrix was increased as increase of Mg additions due to improvement of wettability between SiC particle and matrix. A favorable composites were obtained by melting under Ar atmospheric SiCp injection and bottom pouring system. According to the analysis of X-ray diffraction, $Mg_2Si$, $Al_4C_3$, $SiO_2$ and MgO, etc, intermetallic compounds were formed by chemical interreaction at interface of matrix and particles. The microhardness of interface is higher than that of matrix due to more strengthening of above intermetallic compounds. It was considered that the total hardness of the composites is improved by dispersing of SiCp and addition of Mg.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2000년도 추계학술발표대회 논문집
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• pp.58-62
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• 2000

The fabrication process and analysis of thermal properties of 50~76vo1% SiCp/Al metal matrix composites(MMCs) for heatsink materials in electronic packaging were investigated. The 50~76vo1% SiCp/Al MMCs fabricated by pressure infiltration casting process showed that thermal conductivities were 85~170W/mK and coefficient of thermal expansion(CTE) were ranged 10~6ppm1k. Specially, the thermal conductivity and CTE of 71vo1%SiCp/Al MMCs were ranged 115~156W/mK and 6~7ppm/K. respectively, which showed a improved thermal properties than the conventional electronic packaging materials such as ceramics and metals.

• 한국주조공학회지
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• 제21권1호
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• pp.7-14
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• 2001

The research on new DRA(discontinuous reinforced alloy) and CRA(continous reinforced alloy) composites has been carried out to improve the properties of ceramic fiber and particle reinforced metal matrix composites(MMCs). Effects of alloying elements and aging conditions on the microstructures and aging behavior of Al-Si-Cu-Mg-(Ni)-SiCp composite have been examined. The specimens used in this study were manufactured by duplex process. The first squeeze casting is the process to make precomposite and the second squeeze casting is the process to make final composite. The hardening behavior was accelerated with decreasing the size of SiCp particle in the composites. It is considered that the dislocation density increased with increasing SiCp size, due to the different thermal deformation between Al matrix and SiCp during quenching after the solution treatment. Peak aging time to obtain the maximum hardness in 3 ${\mu}m$ SiCp reinforced Al composite was reduced than that in large size(5, 10 ${\mu}m$) of SiCp because of difference in dislocation density. Aging hardening responce(${\Delta}H$ = $H_{Max}.-H_{S.T}$) of composites was greater than that of unreinforced Al alloy because of higher density of second phases in matrix.

• 한국자동차공학회논문집
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• 제4권4호
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• pp.130-139
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• 1996

The silicon carbide particles reinforced aluminium 6061($SiCp/A\ell$) composites are generally known have wild range of applications from automobiles to airospaces. But, by the results of existing study for $SiCp/A\ell$ composites, there are reports that the fatigue life of $SiCp/A\ell$ composites has improved than $A\ell$matrixes and has not improved then $A\ell$ matrixes. Consequently, in order to perform the reliable life prediction for $SiCp/A\ell$, the properties of probability distribution of fatigue crack initiation life & fracture life, crack growth length in constant number of cycles, crack growth rate in constant stress intensity factor range and m & C value in Paris's fatigue crack growth law and the estimation of statistical parameters have been evaluated by the statistics method.