• Proceedings of the Korean Nuclear Society Conference
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• 2001.05a
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• pp.308.1-308
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• 2001

• Korean Chemical Engineering Research
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• v.50 no.5
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• pp.894-899
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• 2012

In recent years, recycling process has come to be necessary for separating metals, glass fibers and polymer from WPCBs (waste printed circuit boards) due to an increasing amount of electronic device waste. In this study, dimethylformamide (DMF) and attrition mill reactor were used to separate the component such as metals, glass fiber and epoxy resin from WPCBs. Separation of glass fiber from WPCBs was carried out under stirring rates 300~600 revolution per minute (rpm) for 1~2 h as the various agitator. The recycled glass fibers (RGF) were analyzed by thermogravimetric analyzer (TGA) for degree of separation of epoxy resin in the WPCBs. The degree of separation of epoxy resin of WPCBs increased in attrition mill agitator as a mechanochemical process for recycling WPCBs. The RGF separated in the WPCBs was applied as a reinforcement in the RGF/unsaturated polyester composites to reuse as a reinforcement.

• Journal of Powder Materials
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• v.21 no.4
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• pp.307-312
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• 2014

This study is focused on investigating the relation between the particle size of silver flake powder and mechanical milling parameters. Mechanical milling parameters such as ball size, impeller rotation speed and milling time of the attrition ball-mill were controlled to produce silver flake powder. The particle size of the silver flake powder increased with increasing ball size and impeller rotation speed. The change of the particle size of the silver flake powder with mechanical milling parameters was analyzed based on balls motion in the mill container of the attrition ball-mill. The silver flake particles were formed at the elastic deformation area of the ball due to the collision between balls. The change of the particle size of the silver flake powder with mechanical milling parameters well consists with the change of the collision energy of ball with parameters mentioned above.

• Proceedings of the Korean Nuclear Society Conference
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• 2004.10a
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• pp.1037-1038
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• 2004

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.781-785
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• 1998

Material and electrochemical characteristics of petroleum coke of the nongraphitic carbon prepated with attrition milling for 6~48 hours and heat-treatment at $700^{\circ}C$ for 1 hour was investigated. The milling condition affects the particle size distribution, BET specific surface area and interlayer distance of petroleum cokes. Carbon electrode with petroleum cokes prepared at the milling time of 12~24 hours and having average particle size of $6{\sim}8{\mu}m$ showed best electrochemical characteristics form the investigation of cyclic voltammogram and charge-discharge characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.11a
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• pp.332-335
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• 2003

Particle size and piezoelectric characteristics of PNW-PMN-PZT ceramics with the variations in attrition milling conditions were investigated for the piezoelectric transformer application. Particle size and distribution were decreased with increasing milling time. Dielectric constant (${\varepsilon}r$), electromechanical coupling factor (kp), mechanical quality factor (Qm) and density showed the optimum value of 1563, 0.53, 2342, 7.63, respectively at 7h milling time.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.3
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• pp.217-221
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• 2008

In this study, We have been investigated the effect of calcination temperature and high-energy ball-milling of powder influences the $BaTiO_3$-based PTCR(Positive Temperature coefficient Resistance) characteristics and microstructure. The mixed powder was obtained from $BaCO_3$, $TiO_2$, $CeO_2$ ball-milled in attrition mill. The mixed powder was calcine from 1000 $^{\circ}C$ to 1200 $^{\circ}C$ in air and then it was sintered in reduction- re-oxidation atmosphere. As a result, The room-temperature electrical resistivity decreased and increased with increasing calcination temperature. specially, Attrition milled powder could have low room-temperature resistivity and high PTC jump order at 1100 $^{\circ}C$. attrition milling had lower room-temperature resistivity than ball milling. Particle size decreased by Attrition milling of powder influences in calcination temperature and room-temperature resistivity.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.648-652
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• 2005

A super ionic conductor, $K^+$-beta-aluminas, which is known to be difficult to obtain in the form of dense sintered density under atmospheric pressure, was pulverized to 350 nm mean particle size using attrition mill. The sample were pressed into tablet form by uniaxial pressing. The specimen was sintered under atmospheric pressure in powder form. Sintering temperature range was $1400^{\circ}C$ to $1650^{\circ}C$ at $50^{\circ}C$ intervals. Additionally, zone sintering was carried out to control the growth grain at high temperature ($1600^{\circ}C$). The density of specimens that were sintered at $1600^{\circ}C$ and $1650^{\circ}C$, and sintered at $1600^{\circ}C$ by zone sintering were about 93% and 95%, respectively. In the case of the lengthened sintering time to 2 h, the density of specimen was reduced to lower than 90%, since the particles were grown to the duplex microstructure.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2010.03a
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• pp.6-6
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• 2010

In this study, microstructural and piezoelectric characteristics of PNW-PMN-PZT ceramics manufactured using attrition milling method were investigated. Sintering temperature of the ceramics was varied from $980^{\circ}C$ to $1100^{\circ}C$. At the specimen sintered at $1100^{\circ}C$, mechanical quality factor(Qm) and dielectric constant showed the maxinum values of 2,373 and 1438, respectively. At the specimen sintered at $1080^{\circ}C$, electromechanical coupling factot(kp) also showed the maxinum value of 0.524.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.16 no.2 s.93
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• pp.228-234
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• 2005

A magnetic composite as noise absorber of quasi-microwave band was developed. The Fe-Si-Al alloy powder were forged by attrition mill to get flaky shape. The magnetic composite sheet was fabricated in which powders are dispersed in polymer and aligned in the direction perpendicular to electromagnetic wave propagation. The permittivity of magnetic composite is increased as forging time increasing, while the permeability is decreased slightly. The maximum attenuation peak of reflection loss is shifted to lower fiequency range as milling time increasing, and the value of maximum attenuation peak is to get smaller gradually. From these result, we could designed a noise absorber sheet (t=1.0 mm) for quasi-microwave band, which is impedance matched at 1.4 GHz with respect to -8.2 dB reflection 1055.