• Bulletin of the Korean Chemical Society
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• v.35 no.2
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• pp.597-600
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• 2014

In this work, the electromagnetic interference shielding effectiveness (EMI-SE) of carbon nanotube/carbon fiber-reinforced HDPE matrix composites are investigated with various preparation conditions, such as the carbon fiber and carbon nanotube content, the presence of metal additives, as well as mixing speed and time. It was found that the EMI-SE of the composites increased with filler contents and metal additives. These results indicate that the content and length of carbonaceous fillers determine the electric networks in the composites, resulting in the control of the EMI-SE of the composites.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.397-398
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• 2009

In oder to investigate of partial discharge of nano-composites materials, we have studied partial discharge appling voltage from 5 to 30 [kV] to make an artificial defect with the epoxy adding to 0, 0.4, 0.8, and 1.6 [wt%], respectively. The experimental result, we have found that $SiO_2$ of 0.4 (wt%] was superior to others also, it is found that the effect of isolate diagnosis to get the slope for the discharged electric charge distribution.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03b
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• pp.31-31
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• 2010

Nano particles (10nm $SiO_2$) were silane-treated in order to modify the surface characteristics in a epoxy nanocomposite. Then, micro particles ($3{\mu}m$ SiO2) were poured into the epoxy nanocomposite using various mixing process and epoxy/micro-and-nanomixed composites (EMNC) were prepared. The thermal (Tg) and mechanical (tensile and flexural strength) properties were measured by DSC, DMA and UTM and the data was estimated by Weibull plot.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.25 no.11
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• pp.895-901
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• 2012

In order to application for high voltage heavy electric equipments, epoxy/microsilica 60 wt%/nano layered silicate composites (EMNC_60) and epoxy/microsilica 65 wt%/nano layered silicate composites (EMNC_65) respectively was synthesized by our electric field dispersion method and the result was obtained completely dispersion state. Thermal properties such as glass transition temperature (Tg) and thermal expansion coefficient, and DMA characteristics were studied, and mechanical properties such as tensile and flexural tests were performed. AC electrical insulation strength was also tested. The study on thermal property, EMNC_65 was better than EMNC_60 and mechanical, electrical properties much improved EMNC_60 compared with EMNC_65.

• Transactions on Electrical and Electronic Materials
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• v.12 no.3
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• pp.98-101
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• 2011

A 10 nm nano-silica was introduced to a conventional 3 ${\mu}M$ micro-silica composite to develop an eco-friendly new electric insulation material for heavy electric equipment. Thermal and mechanical properties, such as glass transition temperature (Tg), dynamic mechanical analysis, tensile and flexural strength, were studied. The mechanical results were estimated by comparing scale and shape parameters in Weibull statistical analysis. The thermal and mechanical properties of conventional epoxy/micro-silica composite were improved by the addition of nano-silica. This was due to the increment of the compaction via the even dispersion of the nano-silica among the micro-silica particles.

• Journal of Urban Science
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• v.9 no.1
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• pp.7-16
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• 2020

Application of nanomaterials to cementitious composites has been attempted with the rapid development of nanotechnology since the 1990s. Various nanomaterials such as carbon nanotube, graphene, nano-SiO₂, nano-TiO₂, nano-Al₂O₃, nano-Clay, and nano-Magnetite have been applied to cementitious composites to improve the mechanical properties and the durability, and to impart a variety of functionality. In-depth information on the effect of nanomaterials on the hydration reaction, the microstructure, and the mechanical properties of cementitious nanocomposites is provided in the present study. Specifically, this paper mostly deals with the previous studies on the heat evolution characteristics of cementitious nanomaterials at an early age of curing, and the pore and the compressive strength characteristics of cementitious nanocomposites. Furthermore, the effect of nanomaterials on the cementitious nanocomposites was systematically discussed with the reviews.

• Proceedings of the Korean Vacuum Society Conference
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• 2002.06a
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• pp.130-130
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• 2002

• Journal of the Korean Recycled Construction Resources Institute
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• v.8 no.4
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• pp.421-428
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• 2020

Recently, excellent thermal and electrical performance of cementitious composites by mixing nano materials are being studied. The purpose of this study is to research the heat generation and power consumption of rapid hardening nano-cementitious composites. The experiment was carried out after setting the rapid hardening cementitious material, curing day, and supply voltage as parameters. Rapid hardening nano-cementitious materials were classified into cement paste, mortar, and concrete The heat performance of all rapid hardening nano-cementitious composites in curing 1 day has increased over 10℃. The rapid hardening nano-cementitious composites can exhibit heat performance within 1 day. The heat performance of the rapid hardening nano-cementitious composites is maintained after 28 days.

• Journal of Electrical Engineering and Technology
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• v.10 no.4
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• pp.1712-1719
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• 2015

In recent days, there was a significant development on the electrical, thermal, mechanical, physical, chemical, magnetic and optical properties of the polyamide enamel, varnish and other insulating materials by the addition of nano fillers to it. Enamel was used in High Voltage Apparatuses used in Medical Electronics as insulation. Insulating materials determine the life time of the electrical apparatuses. The life time of the insulating materials was improved by the addition of nano fillers to it. Hence the life time of the electrical apparatuses was improved by the mixing of nano fillers to the enamel. In this research, the basic dielectric properties of the enamel and enamel mixed with nano composites of silica and alumina were analyzed and compared with each other. The addition of nano fillers has improved the quality factor and capacitance of the enamel. It was also observed that the addition of nano fillers has reduced the dissipation factor and dielectric losses of the enamel. Heat produced by the dielectric losses was also reduced by adding nano fillers to it.

• Journal of Powder Materials
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• v.12 no.6 s.53
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• pp.406-412
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• 2005

This work is to present a new synthesis of metallic glass (MG)/metallic glass (MG) composites using gas atomization and spark plasma sintering (SPS) processes. The MG powders of $Cu_{54}Ni_6Zr_{22}Ti_{18}$ (CuA) and $Ni_{59}Zr_{15}Ti_{13}Nb_7Si_3Sn_2Al_1$(NiA) as atomized consist of fully amorphous phases and present a different thermal behavior; $T_g$ (glass transition temperature) and $T_x$ (crystallization temperature) are 716K and 765K for the Cu base powder, but 836K and 890K for the Ni base ones, respectively. SPS process was used to consolidate the mixture of each amorphous powder, being $CuA/10\%NiA\;and\;NiA/10\%CuA$ in weight. The resultant phases were Cu crystalline dispersed NiA matrix composites as well as NiA phase dispersed CuA matrix composites, depending on the SPS temperatures. Effect of the second phases embedded in the MG matrix was discussed on the micro-structure and mechanical properties.