• Journal of the Microelectronics and Packaging Society
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• v.18 no.3
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• pp.9-17
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• 2011

Nano-composite solders have been studied to improve the properties of Pb-free solder joints. The nanoparticles in the composite solders were carbon nanotubes(CNTs), metals (Ag, Ni, Cr, etc.), ceramics (SiC, $ZrO_2$, $TiB_2$, etc.). To fabricate the nano-composite solders, mechanical mixing methods and in-situ fabrication method has been used for well-dispersed nano phase. The characteristic properties of the nano-composite solders were high creep resistance, low undercooling, low IMC growth rate and fine microstructures. More researches on the nano-composite solders are required to improve the processibility and the reliability of the nano-composite solder joints.

• Steel and Composite Structures
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• v.33 no.5
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• pp.653-661
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• 2019

In this paper aeroelastic behavior of 3-phase nano-composite beam-plate with double delaminations is investigated. It is tried to study the effect of carbon nano-tubes (CNTs) on critical flutter pressure of reinforced damaged nano-composite structures. In this case, the CNTs are appending to the polymer matrix uniformly. The Eshelby-Mori-Tanaka model is used to obtain the effective material properties of 3-phase nano-composite beam-plate. To investigate the aeroelastic behavior of delaminated beam-plate subjected to supersonic flow, it is assumed that the damaged segments are forced to vibrate together. The boundary conditions and auxiliary conditions at edges of delaminated segments are used to predict critical flutter pressure. The influence of CNTs and different delamination parameters such as delamination length, axial position and its position through thickness are investigated on critical flutter pressure.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.55-58
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• 2003

This paper presents a study on the permittivities of the carbon nano fiber/epoxy composite at microwave frequency. The permittivities of composite materials depend on the concentrations and the dispersion methods of the carbon nano fibers. The experimental values of complex permittivities were obtained for the specimen made by dispersion method using ethyl alcohol as dispersion media and compared with the results by simple mechanical mixing method.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.374-375
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• 2008

In this study, the nano-composite actuator based on Fullerene and Nafion was newly developed to improve the electro active polymer actuators. The tensile test was employed to define the mechanical stiffness and strength of the nano-composite membrane. Also, the bending displacement of the Fullerene-Nafion based nano-composite actuator was investigated under DC and AC excitations with various magnitudes and frequencies. As a result, the new nano-composite actuator based on Fullerene-Nafion shows much larger deformation than the pure Nafion based actuator and solves the straightening back Problem of the previous electro active polymer actuators.

• Journal of Power System Engineering
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• v.13 no.1
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• pp.65-71
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• 2009

To address the need for new intelligent sensing, this paper introduces nano sensors made of carbon nanotube (CNT) composites and presents their preliminary experiments. Having smart material properties such as piezoresistivity, chemical and bio selectivity, the nano composite can be used as smart electrodes of the nano sensors. The nano composite sensor can detect structural deterioration, chemical contamination and bio signal by means of its impedance measurement (resistance and capacitance). For a structural application, the change of impedance shows specific patterns depending on the structural deterioration and this characteristic is available for an in-situ multi-functional sensor, which can simultaneously detect multi symptoms of the structure. This study is anticipated to develop a new nano sensor detecting multiple symptoms in structural, chemical and bio applications with simple electric circuits.

• Fashion & Textile Research Journal
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• v.12 no.6
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• pp.837-842
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• 2010

This study examines the dyeability, light fastness, washing fastness, and antibacterial activity of chitosan and nano silver composite knit fabrics dyed with extracted solution from Chrysanthemum Indicum Linn. The results show that ${\Delta}E$ values of chitosan and nano silver composite knit fabrics were higher than cotton 100% knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn, and mordant treatments influenced the chrominance change. Chrysanthemum indicum Linn confirmed that this could be a polygenetic colors. ${\Delta}E$ values of post-mordant treatments knit fabrics were higher than pre-mordant treatments knit fabrics in dyed condition with extracted solution from Chrysanthemum Indicum Linn., and mordant treatments method influenced the chrominance change. The dyeability of chitosan and nano silver composite knit fabrics was increased by mordant treatment. The fastness of the chitosan and nano silver composite knit fabrics was better than cotton 100% knit fabrics. In the result of antibacterial activity, the bacterial reduction rate of chitosan and nano silver composite knit fabrics was 99.9% to Staphylococcus aureus and Klebsiella pneumoniae.

• Proceedings of the Korean Ceranic Society Conference
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• 2004.04b
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• pp.50.3-50.3
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• 2004

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.23 no.2
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• pp.67-74
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• 2017

In this work, the effects of nano $TiO_2$ on functionality and stability of low density polyethylene (LDPE) composite films were investigated for food packaging application. LDPE-nano $TiO_2$ composite films were prepared with various $TiO_2$ contents (0, 0.5, 1.0, 3.0 and 5.0wt%) by melt-extrusion and their basic properties such as crystallinity, chemical bonds and surface morphology were examined by XRD, FTIR and SEM. Ultraviolet (UV) light barrier property of as-prepared LDPE-nano $TiO_2$ composite films was also studied and the presence of nano $TiO_2$ resulted in significant improvement of UV light barrier compared to the pure LDPE film. To evaluate influence of nano $TiO_2$ on LDPE properties required as packaging material, thermal, mechanical, gas barrier and optical properties of LDPE-nano $TiO_2$ composite films were characterized with various analytical techniques including TGA, UTM, OTR, WVTR and UV-vis spectroscopy. As a result, except optical property of LDPE, no significant effects were found in other properties. Opacity of pure LDPE was greatly increased with increasing concentration of nano $TiO_2$.

• Proceedings of the Materials Research Society of Korea Conference
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• 2010.05a
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• pp.26.1-26.1
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• 2010

Ni-SiC nano composite coatings were fabricated using electrodeposition technique with the aid of ultrasound. The properties of the nano composite were investigated by using SEM, XRD, Wear test and Vicker's microhardness test. The results demonstrated that the microhardness of composite coatings under ultrasonic condition was improved significantly as compared to conventional electrodeposition techniques without ultrasound. The nano particles were found to be distributed homogeneously with reduced agglomeration. The synergistic combination of superior wear resistance and improved microhardness was found in ultrasonicated conditions to the Ni-SiC nano composite coatings.

• Corrosion Science and Technology
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• v.18 no.1
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• pp.16-23
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• 2019

Steels for automotive fuel tank require unique properties such as corrosion resistance for fuel, welding for joining, forming for press, and painting for exterior. Recently, automakers have been requiring excellent seam weldable steels to enhance manufacturing productivity of fuel tank. Thus, POSCO developed a new type of functional steels coated with nano-composite thin layer on Zn-Ni plating steels. The nano-composite coating solution was prepared by mechanical fine dispersion of solutions consisting of polymeric resin and nano-composite materials in aqueous media. The composite solution was coated on the plating steel surface by using roll coater and cured through induction furnace. These new developed plating steels were evaluated for quality performances such as seam and spot weldability, press formability, and corrosion resistance. These new functional steels coated with nano-composite layer exhibited excellent seam weldability and press formability. Detailed discussion of coating solution and experimental results suggest that nano-sized composite dispersion as coating layer plays a key role in enhancing the quality performance.