• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.3
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• pp.570-575
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• 2002

It is well-known that the bond strength between CFRP(Carbon Fiber Reinforced Plastic) and aluminum is significantly affected by the surface treatment of the CFRP and the aluminum. This study investigates the surface treatment of CFRP to improve the T-peel strength of CFRP/aluminum composites. The surface of %CFRP([0^0]_{14})$ was treated by the ion assisted reaction method under oxygen environment. T-peel strength tests were performed based on the procedure of ASTM D1876-95. The T-peel strength of surface-treated CFRP/aluminum composites was compared with that of untreated CFRP/aluminum composites. The results showed that the T-peel strength of surface-treated CFRP/aluminum composites was about 5.5 times higher than that of untreated CFRP/aluminum composites. SEM examination showed that the improvement of T-peel strength was attributed to the uniform spread and fracture of epoxy adhesive.

• Journal of the Korean Vacuum Society
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• v.6 no.3
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• pp.200-205
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• 1997

Surface of polyethylene film was modified by ion assisted reaction in which ion beam is irradiated on polymer in reactive gas environments. Ion (argon and oxygen) beam energy was 1 keV, doses were varied from $1{\times}10^{14}$ to $1{\times}10^{17}$ inons/ $\textrm{cm}^2$, and amount of blowing oxygen from 0 to 4 sccm(ml/min). Wettability was measured by water contact angle measurement, and the surface functionality was analyzed by x-ray photoelectron spectroscopy. The contact angles of water to polyethylene modified by oxygen ion beam only decrease from 95 to degrees, and surface energy was not changed much. The contact angles remarkably decrease to 28 degrees and surface energy increase to 67 erg/ $\textrm{cm}^2$ when the films were modified by argon ion with various ion doses with blowing oxygen gases near the polyethylene surface. Improvement of wettability and surface energy are mainly due to the new functional group formation such as C-O or C=O, which are known as hydrophilic groups from the XPS analysis, and the assisted reaction is very effective to attach oxygen atoms to form functional groups on C-C bond chains of polyethylene.

• Journal of the Microelectronics and Packaging Society
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• v.8 no.1
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• pp.53-59
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• 2001

Surfaces of PTFE and PVDF were modified by ion-assisted reaction (IAR) in which 1 keV $Ar^{+}$ ions were irradiated on the surface of the polymer with varying ion dose in an oxygen gas environment, and Cu, Pt, Al and Ag thin films were deposited on the modified polymers. Wettability of the modified polymers was largely improved by the formation of hydrophilic groups due to chemical reaction between polymer surface and the oxygen gas during IAR. The change in wettability in the modified polymers was also related to the change in surface morphology and roughness. Adhesion between metal films and polymers modified by IAR was significantly improved, so that no detachment was possible in the $Scotch^{TM}$ tape test. The increase of adhesion strength between the metal film and the modified PVDF was mainly attributed to the formation of hydrophilic groups, which interacted with the metal film. In the case of the modified PTFE, the enhanced adhesion to metal film could be explained by the change in surface morphology together with the formation of hydrophilic groups. The electrical properties of the metal films on the modified polymers were also investigated.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.8
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• pp.122-128
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• 2001

The objective of the present study was to investigate the characteristics of the friction and wear according to the amount of ion-irradiation for the carbon fiber reinforced plastic(CFRP). Unidirectional carbon fiber reinforced composites were fabricated with epoxy resin as a matrix and carbon fiber as a reinforcement, and its surface was modified by the ion-assisted reaction. When the amount of ion-irradiation was $1{\times}10^{16}$ ions/$cm^2$, the friction coefficients of composites were about 0.1 and the wear mode was stable, whereas, the friction coefficient of non-treatment composites were about 0.16 and the wear mode was very unstable. But if the amount of ion-irradiation was $5{\times}10^{16}$ ions/$cm^2$, the friction coefficients were higher rather than that of $1{\times}10^{16}$ ions/$cm^2$. Consequently, the amount of ion-irradiation was not in proportion to the friction coefficients, and it was conformed that the optimal conditions would exist between broth of them.

• Tribology and Lubricants
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• v.18 no.1
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• pp.61-67
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• 2002

The objective of the present study was to investigate the characteristics of the friction and wear according to the amount of ion-irradiation for the carbon fiber reinforced plastic (CFRP). Unidirectional carbon fiber reinforced composites were fabricated with epoxy resin as a matrix and carbon fiber as a reinforcement, and its surface was modified by the ion-assisted reaction. When the amount of ion-irradiation was $1{\times}10^{16}$ $ions/cm^{2}$. the friction coefficients of composites were about 0.1 and the wear mode was stable. whereas, the friction coefficient of non-treatment composites were about 0.16 and the wear mode was very unstable. But if the amount of ion-irradiation was $5{\times}10^{16}$ $ions/cm^{2}$, the friction coefficients were higher rather than that of $1{\times}10^{16}$ $ions/cm^{2}$ Consequently. the amount of ion-irradiation was not in proportion to the friction coefficients, and it was conformed that the optimal conditions would exist between both of them.

• Polymer(Korea)
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• v.26 no.6
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• pp.718-727
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• 2002

In this work, an Ar+ beam was irradiated on carbon fiber surfaces to improve the interfacial shear strength (IFSS) of the resulting composites using an ion assisted reaction (IAR) method h single fiber pull-out test was executed to investigate the basic characteristics of the single Carbon fiber/matrix interface. Based on Greszczuk's geometrical model, the debonding force for pull-out of the fiber from the resins was discussed with the applied ion beam energy as a result, it was known that an ion beam treatment produced the functional groups on fiber surface and etching lines along the fiber axis direction, resulting in increasing the adhesion forces between fibers and matrix, which caused the improvement of the IFSS in a composite system. And, it was also found that the maximum IFSS was shown at 0.8 keV ion beam energy in this system.

• 한국생물공학회:학술대회논문집
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• 2003.10a
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• pp.782-782
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• 2003

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2001.07a
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• pp.142-145
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• 2001

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2004.06a
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• pp.32-42
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• 2004

Recently, plasma surface-cleaning or surface-etching techniques have been focused in respect of the decontamination of spent or used nuclear parts and equipment. In this study the removal rate of metallic cobalt surface is experimentally investigated via its surface etching rate with a $CF_4-o_2$mixed gas plasma. Experimental results reveal that a mixed etchant gas with about 80% $CF_4$-20% $O_2$ (molar) gives the highest reaction rate and the rate reaches 0.06 ${\mu}m$/min at $380^{\circ}C$ and ion-assisted etching dramatically enhances the surface reaction rate. With a negative 300 V DC bias voltage applied to the substrate, the surface reaction initiation temperature lowers and the rate increases about 20 times at $350^{\circ}C$ and up to 0.43 ${\mu}m$/min at $380^{\circ}C$, respectively. Surface morphology analysis confirms the etching rate measurements. Auger spectrum analysis clearly shows the adsorption of fluorine atoms on the reacted surface. From the current experimental findings and the results discussed in previous studies, mechanistic understanding of the surface reaction, fluorination and/or fluoro-carbonylation reaction, is provided.

• Korean Chemical Engineering Research
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• v.51 no.4
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• pp.460-464
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• 2013

A series of Mn compound were prepared by seed-assisted method. The seed used in this reaction was manufactured by calcination of $MnCO_3$ at various temperatures and effects of the calcination temperature on seed-assisted reaction were investigated. With increase of the calcination temperature, CMD (${\gamma}-MnO_2$) was recovered after seed-assisted reactions. LMO used as cathode active material in the Li-ion batteries were synthesized from Mn source obtained in the seed-assisted reaction and the electrochemical properties (rate capability, cycle life performance and specific capacity) of the LMO were investigated. The LMO synthesized from the CMD which is obtained by the reaction with seed prepared by calcination of $MnCO_3$ more than $350^{\circ}C$ shown good electrochemical properties.