• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1998.05a
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• pp.91-92
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• 1998

• Journal of the Korean Magnetics Society
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• v.15 no.2
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• pp.67-75
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• 2005

For th aim of lightweight microwave absorbers, conductive and magnetic microspheres are fabricated by plating of Co films on hollow ceramic microspheres of low density. Metal plating was carried out in a two-step electroless plating process (pre-treatment of activation and plating). Uniform coating of the film with about $2{\~}3{\cal}um$ thickness was identified by SEM. High-frequency magnetic and microwave absorbing properties were determined in the rubber composites containing the Co-coated microspheres. Due to conductive and ferromagnetic behavior of the Co thin films, high dielectric constant and magnetic loss can be obtained in the microwave frequencies. Due to those electromagnetic properties, high absorption rate (25 dB) and thin matching thickness ($2.0{\~}2.5{\cal}mm$) are predicted in the composite layers containing the metal-coated microspheres of low density (about 0.84 g/cc) for the electromagnetic radiation in microwave frequencies.

• Journal of the Korean institute of surface engineering
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• v.19 no.2
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• pp.59-64
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• 1986

Pulse current was empolyed to the chromium electroplating bath of self-regulating high speed in the following range of conditions; 10-80$^{\circ}C$, 0-400A/$dm^2$, 10-100KHz. The current efficiency was compared with that of a conventional direct current plating in respect of current density and electrode interdistance. The effect of pulse current was found to increase the current efficiency at least 10-20 percent more than the conventional direct current plating in the high current density more than 100A/$dm^2$ and at 3-4mm of electrode interdistance. The surface appearance was also studied and known to be of great influenced by pulse frequency.

• Journal of the Korean Ceramic Society
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• v.45 no.12
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• pp.807-814
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• 2008

The Cu-Ni-YSZ cermet anodes for direct use of methane in solid oxide fuel cells have been fabricated by electroplating Cu into the porous Ni-YSZ cermet anode. The uniform distribution of Cu in the Ni-YSZ anode could be obtained via pulse electroplating in the aqueous solution mixture of $CuSO_4{\cdot}5H_{2}O$ and ${H_2}{SO_4}$ for 30 min with 0.05 A of average applied current. The power density ($0.17\;Wcm^{-2}$) of a single cell with a Cu-Ni-YSZ anode was shown to be slightly lower in methane at $700^{\circ}C$, compared with the power density ($0.28\;Wcm^{-2}$) of a single cell with a Ni-YSZ anode. However, the performance of the Ni-YSZ anode-supported single cell was abruptly degraded over 21 h because of carbon deposition, whereas the Cu-Ni-YSZ anode-supported single cell showed the enhanced durability upto 52 h.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.4
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• pp.291-299
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• 2009

Ni-plated polytetrafluoroethylene(Ni-PTFE) particles($25{\mu}m$, $500{\mu}m$) were prepared by using nickel electroless plating. The Ni content in Ni-PTFE particles increased with increasing the amount of reduction agent. At about 53 wt% Ni content, $25{\mu}m$ Ni-PTFE particles showed conductivity of 320S/m. The Ni-PTFE particles were formed into the Ni-PTFE plate using heat treatment at $350^{\circ}C$ under $10{\sim}1000kg/cm^2$. The Ni-PTFE plate displayed the high conductivity of 5100S/m due to the formation of 3-dimentional Ni network. The plate was used as an electrode in an alkaline fuel cell(AFC). In terms of the current density, the Ni-PTFE electrode having higher Ni content(53 wt%) showed improved performance.

• Journal of the Microelectronics and Packaging Society
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• v.15 no.4
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• pp.71-76
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• 2008

The mechanical properties of Ni-Fe alloy were varied with the current type, current density and bath conditions such as concentrations and temperature. The effect of electroplating parameters on the surface hardness, mechanical strength, residual stress and wear properties were investigated. The mechanical properties of electrodeposits with PC plating is superior to those with DC plating. Ni-Fe electrodeposits with PC has approximately 50% lower residual stress than that of DC plating. The tensile strength of PC electroplated specimen was 15% higher than that of DC electroplated specimen. The wear resistance of PC specimen was 30% improved relative to that of DC specimen.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.909-911
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• 1999

Metalization technology of the fine patterns by electroless plating is required in place of electrodeposition as high-density printed circuit boards (PCB) become indispensable with the miniaturization of electronic components. Electroless nickel plating is a suitable diffusion barrier between conductor metals, such as Al and Cu, and solder is essetional in electronic packaging in order to sustain a long period of service. Moreover, Electroless nickel has particular characteristics including non-magnetic property, amorphous structure, wear resistance, corrosion protection and thermal stability. In this study fundamental aspects of electroless nickel deposition were studied with effect of complexeing agents of different kinds. Then, the property of electroless deposit are controlled by the composition of the deposition solution, the deposition condition such as temperature and pH value and so on. the characteristics of the deposits has been carried out.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2017.05a
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• pp.123.1-123.1
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• 2017

Hybrid solar cells have intensively studied in recent years due to their advantages such as cost effectiveness and possibility of applications in flexible and transparent devices. It is critical to fabricate individual layer composed of organic and inorganic materials in the hybrid solar cell at low cost. Therefore, it is required to manufacture cheaply and enhance the photon-to-electricity conversion efficiency of each layer in the flexible solar cell industry. In this research, we fabricated pure Cu metal mesh electrode prepared by using electroplating and/or electroless plating on the Ni mold which was manufacture through photolithography, electroforming, and polishing process. Copper mesh was formed on the surface of nickel metal working master when pulsed electrolytic copper deposition were performed at various plating parameters such as plating time, current density, and so on. After electrodeposition at 2ASD for 5~30seconds, the line/pitch/thickness of copper mesh sheet was $1.8{\sim}2.0/298/0.5{\mu}m$.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.545-548
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• 1996

$CrN_x$ films were deposited on SKD61 and S45C by cathodic arc ion plating process. In this study, the microstructure, microhardness, a hesion, wear and corrosion properties of the CrNx films were studied for various nitrogen partial pressures and the results were compared with those from the electroplated hard Cr. The crystal structure of the films was characterized by X-ray diffraction. Wear tests were performed under no lubricant condition at atmosphere by ball-on-disc type tribotester. Corrosion resistance of the films were studied by electrochemical corrosion test, measuring current demsity-potential curves. The results indicated that the $CrN_x$ films formed using ion plation method showed higer hardness and lower current density, friction coefficient than electroplated hard Cr. Consequently, the application of the CrNx coationgs by ion plating which is free of environmental pollution, is expected to improve lifetime of components in industrial practice.

• Journal of the Korean institute of surface engineering
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• v.51 no.5
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• pp.263-270
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• 2018

Ag-coated Cu dendrites were prepared as a filler for an electromagnetic interference shielding application. Ag layers on the Cu dendrites was coated by two approaches. One is a direct autocatalytic plating with a reducing agent. The other approach was achieved by two-step plating, a galvanic displacement reaction to form Ag seed layers on Cu following by an autocatalytic plating with a reducing agent. The procedure-dependent average particle size and tap density of Ag-coated Cu dendrites were characterized. The electrical resistance and electromagnetic interference shielding effect (EMI SE) were analyzed with the Ag-coated Cu dendrites prepared in the two approaches. Additionally, the content of the Ag coated on Cu dendrites was controlled from 2% to 20%. The electrical resistance and EMI SE were critically determined by Ag contents coated on Cu.