• Composites Research
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• v.25 no.4
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• pp.93-97
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• 2012

Carbon nano fibers (CNFs) reinforced magnesium alloy (AZ91) matrix composites have been fabricated by liquid pressing process. In order to improve the dispersibility of CNFs and the wettability with magnesium alloy melt, CNFs were mixed with submicron sized SiC particles ($SiC_p$). Also, the mixture of CNFs and $SiC_p$ were coated with Ni by electroless plating. In liquid pressing process, AZ91 melts have been pressed hydrostatically and infiltrated into three reinforcement preforms of only CNFs, the mixture of CNFs and $SiC_p$ (CNF+$SiC_p$), and Ni coated CNFs and $SiC_p$ ((CNF+$SiC_p$)/Ni). Some CNFs agglomerates were observed in only CNFs reinforced composite. In cases of the composites reinforce with CNF+$SiC_p$ and (CNF+$SiC_p$)/Ni, CNFs were dispersed homogeneously in the matrix, which resulted in the improvement of mechanical properties. The compressive strengths of CNF+$SiC_p$ and (CNF+$SiC_p$)/Ni reinforced composites were 38% and 28% higher than that of only CNFs composite.

• 한국문화재보존과학회:학술대회논문집
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• 2007.05a
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• pp.15-17
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• 2007

• Korean Journal of Materials Research
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• v.5 no.2
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• pp.215-222
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• 1995

Anisotropic pitch-based C-type and hollow carbon fibers can obtain wider shear stresses during the spinning and induce higher molecular orientation than that of round along the fiber axis. These fibers reinforced unidirectional epoxy composites were prepared by hot-press moulding method and perpendicular and parallel thermal conductivities of the composites were measured by a steady-state meth od. In the case of round carbon fibers reinforced epoxy composites(H-CF/EP), thermal anisotropic factor showed nearly 50, while those of H-CF/EP and C-CF/EP showed about 130 and 118, respectively. As a result, both H-CF/EP and C-CF/EP had an excellent directional thermal conductivity to distribute heat, above 200 %.

• Analytical Science and Technology
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• v.22 no.3
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• pp.263-271
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• 2009

The purpose of metal artifacts conservation is recovering the original state of objects and preventing it from further corrosion. Four different consolidants are selected that are widely used for bronze objects conservation. This study found out the characteristics of thin film by various experiments and analysis for the bronze plates coated using each solutions. After a series of analysis, resin B and V showed good coating properties. However, the evaluation point suited to this purpose are adhesive strength, stability against yellowing and corrosion resistance. Therefore, resin B of four different consolidants could expect to get the most suitable consolidation effect for consolidation purpose.

• Journal of Conservation Science
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• v.20
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• pp.81-88
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• 2007

For the conservation of wooden coffin from King Muryeong's Tomb we examined weight change, shrinkage rate, color changes, and permeation expansion according to the permeation pretreatment chemicals by producing experimental samples with similar physical properties. The result shows Dammar 2 %(in xylene) as the most excellent treatment for protecting deformation by contraction and strengthening materials which are also maintaining its original colors of wood. Therefore, we could get strengthening conservation treatments of dried wooden coffin materials by using Dammar.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.96-96
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• 2004

고성능 섬유강화 복합재는 비강성과 비강도가 높고 내부식성과 피로특성이 우수하지만 외부에서 가해지는 하중에 의해 수지, 강화섬유와 수지와의 경계면, 적층 경계면 등에 육안으로 식별하기 어려운 손상이 유발될 가능성이 있으며 이로 인해 구조재로서의 역할을 하지 못하는 경우가 발생한다. 최근에는 외부하중으로 인해 복합재 구조재에 손상이 발생한 경우 자가치료제가 저장된 마이크로캡슐을 이용하여 손상을 보수하려는 시도가 행해지고 있다.(중략)

• 한국문화재보존과학회:학술대회논문집
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• 2002.11a
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• pp.31-40
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• 2002

1. 프랑스의 문화재보존과 복원 연구소 조직 현황소개 2. ARC-NUCLEART연구소 소개-연구소에서 문화재 보존을 위해서 사용 기술소개 - 지상과 해양의 고고학 발굴시 젖은 목재와 가죽작품 건조작업, 강화작 업, 보수작업 수행 -목재문화재 (조각상, 가구, 사적 바닥마루), 멸균 및 강화처리 - 가죽문화재의 복원 3. 연구소 시설 4. 화재 자질의 파손상태파악과 고고학가치의 목재와 가죽작품 보존 방법에 대한 연구 수행 5. ARC-NUCLEART에서 보존, 복원하는 문화재의 처리 용례 아크 뉘클레아르(ARC Nucleart)의 감마선조사기 설치

• Composites Research
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• v.16 no.3
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• pp.1-8
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• 2003

Densification occurs by the inelastic flow of the matrix materials during the consolidation processes at high temperature for MMCs, and the results depend on many process conditions such as applied pressure, temperature and volume fraction of fiber and matrix materials. This is particularly important in titanium matrix composites since material failure may occur by either the applied conditions or microstructural parameters through the processes, and thus a generic model based on micro-mechanical approaches enabling the evolution of density over time to be predicted has been developed. The mode developed is then implemented into FEM so that practical process simulation has been carried out. Further the experimental investigation of the consolidation behavior of SiC/Ti-6Al-4V composites using vacuum hot pressing has been performed, and the results obtained are compared with the model predictions.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.7
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• pp.745-751
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• 2011

This study proposes finite element modeling of dislocation punching at cooling after consolidation in order to calculate the strength of particle-reinforced aluminum composites. The Taylor dislocation model combined with strain gradient plasticity around the reinforced particle is adopted to take into account the size-dependency of different volume fractions of the particle. The strain gradients were obtained from the equivalent plastic strain calculated during the cooling of the spherical unit cell, when the dislocation punching due to CTE (Coefficient of Thermal Expansion) mismatch is activated. The enhanced yield stress was observed by including the strain gradients, in an average sense, over the punched zone. The tensile strength of the SiCp/Al 356-T6 composite was predicted through the finite element analysis of an axisymmetric unit cell for various sizes and volume fractions of the particle. The predicted strengths were found to be in good agreement with the experimental data. Further, the particle-size dependency was clearly established.

• 한국문화재보존과학회:학술대회논문집
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• 2006.04a
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• pp.75-77
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• 2006