• Journal of the Korean Society for Precision Engineering
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• v.20 no.8
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• pp.153-157
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• 2003

In the present work, the effect of plasma treatment of aluminum on the fracture toughness of CFRP/aluminum composites was investigated. The surface of the aluminum was treated by a DC plasma. The plasma treatment was carried out at volume ratio of acetylene gas to nitrogen gas of 5:5 and the treatment time used was 30 sec. Cracked lap shear specimens of aluminum/CFRP composites were made using secondary bonding procedure. Fracture toughness of aluminum/CFRP composites was determined using the work factor approach. Then, the fracture toughness of plasma-treated aluminum/CFRP composites was compared with that of untreated aluminum/CFRP composites. The results showed that the fracture toughness of plasma-treated aluminum/CFRP composites was about 50 % higher than that of untreated aluminum/CFRP composites.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.4
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• pp.632-637
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• 2003

In this study, the effect of surface treatment of CFRP and aluminum on the fracture toughness of CFRP/aluminum composites was investigated. CFRP was surface-treated by Ar$^{+}$ ion beam under oxygen environment, and the aluminum was surface-treated by DC plasma. CFRP was adhesively bonded to aluminum using the secondary bonding procedure. Cracked lap shear specimens were used to determine fracture toughness. Three cases of cracked lap shear specimens were made depending on the surface treatment. The values of fracture toughness of three cases were compared to each other It was found that the fracture toughness of ion beam-treated CFRP/aluminum composites was almost 72 % higher than that of unrented CFRP/aluminum composites. The fracture toughness of CFRP/plasma-treated aluminum composites was 50 % higher than that of untreated CFRP/aluminum composites.s.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.401-404
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• 2003

This paper investigates the effect of plasma treatment of aluminum on the fracture toughness of aluminum/CFRP composites, The surface of the aluminum panel was treated by a DC plasma. The plasma treatment was carried out at volume ratio of acetylene gas to nitrogen gas of 5:5 and the treatment times used was 30 sec. The fracture toughness of plasma-treated aluminum/CFRP' composites was compared with that of untreated aluminum/CFRP composites and The fracture surface of aluminum/CFRP composites was compared with SEM. The results showed that fracture toughness of plasm-treated aluminum/CFRP composites was about 50% higher than that of untreated aluminum/CFRP composites.

• 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.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.12
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• pp.1981-1987
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• 2001

This paper documents the effect of surface treatment of aluminum on the bonding strength of aluminum/CFRP composites. The surface of aluminum panel was treated by DC plasma. The optimal treatment condition of the aluminum was determined by measuring the contact angle and T-peel strength as functions of mixture ratio of acetylene gas to nitrogen gas. The mixture ratios used were 1:9, 3:7, 5:5, 7:3, and 9:1 Lap shear tests and T-peel tests were performed using surface-treated alumiunm/CFRP composites and regular alumiunm/CFRP composites. The results showed that the contact angle was minimized and the T-peel strength was maximized iota the mixture ratio of 5:5. The results also showed that the shear strength of surface-treated alumiunm/CFRP composites was 34% greater than that of regular alumiunm/CFRP composites. The T-peel strength of surface-treated alumiunm/CFRP composites was also 5 times greater than that of regular alumiunm/CFRP composites.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.7 no.4
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• pp.10-16
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• 2008

This study investigated electromagnetic interference(EMI) shielding effectiveness(SE) of the aluminum film, conductive fabric and nano carbon black carbon fiber reinforced composites. We fabricated carbon fiber reinforced composites filled with nano carbon black where they bonded aluminum film and conductive fabric. The measurements of SE were carried out frequency range from 300MHz to 1.5GHz. It is observed that the SE of the bonded aluminum film and conductive fabric composites is the frequency dependent, increase with the increase in filler nano carbon black content. The aluminum film bonded composites showed higher SE compared to that of carbon black and conductive fabric. The aluminum film bonded epoxy composite was shown to exhibit up to 80dB of SE. The result that aluminum film bonded composite can be used for the purpose of EMI shielding as well as for some microwave applications.

• Journal of the Korea Institute of Military Science and Technology
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• v.21 no.5
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• pp.591-598
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• 2018

The reaction characteristics of aluminum-copper(II) oxide composites initiated by the electrostatic discharge were studied as changing the aluminum particle size. Three different sizes of aluminum particles with nano-size copper(II)-oxide particle were used in the study. These composites were manufactured by two methods i.e. a shock-gel method and a self-assembly method. The larger aluminum particle size was, the less sensitive and less violent these composites were based on the electrostatic test. On the analysis of high speed camera about ignition appearances and burning time, the burning speed was faster when aluminum particle size was smaller.

• Journal of Korea Foundry Society
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• v.17 no.2
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• pp.164-169
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• 1997

Mechanical properties of aluminum-matrix composites, fabricated by dispersion of fine SiC particulates of which size was less than 1 ${\mu}m$ into 2024 and 7075 aluminum alloys, have been investigated. Homogeneous mixing between the matrix and SiC particulates could be achieved by jar milling for 8 hours with appropriate processing agent. At temperatures below 473K, high-temperature tensile strength of the composites was higher than that of the 2024 and 7075 aluminum alloys which were used as matrix materials. However, tensile strength of the composites was approximated to that of the matrix materials at 573K. Thus, it could be suggested that effects of particle dispersion on tensile strength of aluminum alloys was diminished at temperatures higher than 573K.

• Journal of the Korean institute of surface engineering
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• v.34 no.1
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• pp.56-61
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• 2001

In this work, the surface treatment of aluminum/composites (graphite-epoxy composites) was investigated. The surface of composites was treated by $Ar^{+}$ ion beam under oxygen environment. The surface of aluminum was treated by DC plasma. The optimal condition of surface treatment for the composites was determined by measuring the contact angle as a function of ion dose. The optimal treatment condition of the aluminum was determined by measuring the contact angle and T-peel strength as a function of mixture ratio of acetylene gas to nitrogen gas. The mixture ratios used were 1:9, 3:7, 5:5, 7:3, and 9:1. The results showed that the contact angle of composites decreased from$ 81^{\circ}$ to $8^{\circ}$ as the ion dose increased from zero to $1$\times$10^{17}$ions/$\textrm{cm}^2$. The optimal condition of ion dose was $1$\times$10^{16}$ions/$\textrm{cm}^2$. The results also showed that the contact angle of aluminum was a minimum for the mixture ratio of 5:5. Similarly, the T-peel strength was a maximum for the mixture ratio of 5:5, which indicates that the optimal condition of mixture ratio of acetylene gas to nitrogen gas is 5:5.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.2644-2649
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• 2011

The purpose of this study is to propose the modular design of hybrid lightweight carbody structures made of sandwich composites and aluminum extrusion. The sandwich composites were used for secondary structures to minimize the weight of carbody, and the aluminum extrusions were applied to primary structures to improve the stiffness of carbody and manufacturability. Key requirements were defined for the modular design of hybrid carbody, and the applied parts of sandwich composites were determined through the topology optimization analysis. Consequently, feasibility of enhancing mass saving and maintainability in modular hybrid carbody design were presented, comparing with the carbody structures made of aluminum extrusion or sandwich composites only.