• Proceedings of the Korean Society For Composite Materials Conference
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• 2004.10a
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• pp.159-162
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• 2004

The processing of phenolic composite reinforced with hybrid of PAN based/Rayon based carbon fabrics using FBG sensor and thermocouple was studied. Once the composite is cured, the reflection spectrum from the FBG sensor shifted the center wavelength with an increase in the temperature. Also, the change in the form of the reflection spectrum obtained during the cooling process of the cure cycle was caused by the thermal shrinkage. During the curing process, uniform distribution of the temperature profile was observed throughout the sample.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2005.11a
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• pp.219-223
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• 2005

In this work, a hybrid composite proceeding bearing (HCJB) composed of carbon/phenolic laminated composite bush and steel housing was designed for marine vessels because the composite proceeding bearing reduces the possibility of the seizure problem between the proceeding and bearing. The two components of bearing were assembled by interference fit joining method and a series of durability tests were conducted using the laboratory bench with the lubricants of SAE 30 oil, water, and sea water. That the HCJB was found reliable under the interference fitting loads and environmental temperature change.

• Journal of the Korean Ceramic Society
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• v.33 no.8
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• pp.935-941
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• 1996

Two-dimensional carbon/carbon preforms made of PAN-based carbon yarn and phenolic resin were densified with pyrolysis of propane by pulse chemical vapor infiltration where repeated the cycle of gas introduction residence and evacuation. Maximim density increment was 14% when infiltration temperature and time were 100$0^{\circ}C$ and 21.25 hrs respectively. The distribution of deposits of pyrocarbon by this process has been occurred uniformly in the bottom middle and top of carbon/carbon composite preform Pulse CVI with residence is most effective in increasing density and shortening infiltration time among isothermal CVI and pulse CVI with and without residence.

• Carbon letters
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• v.7 no.1
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• pp.27-33
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• 2006

Carbon-ceramic composites were fabricated by using fly ash and PANOX fibers as reinforcement. Fly ash, because of its small size particles e.g. submicron to micron level can be effectively dispersed along with fibrous reinforcements. Phenolic resin was used as carbon precursor. Both dry as well as wet methods were used for forming composites. The resulting composites were characterized for their microstructure, thermal and mechanical properties. The microstructure and mechanical properties of composites are found to be dependent on type of the fly ash, fibrous reinforcements as well as processing parameters. The addition of fly ash improves hardness and the fibers, which get co-carbonized on heat treatment, increase the flexural strength of the carbon-ceramic composites. Composites with dual reinforcement exhibit about 30-40% higher strength as compared to the composites made with single reinforcement, either with fly ash as filler or with chopped fibers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.3
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• pp.89-95
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• 2022

In this study, glassy carbon coating was performed on the graphite using a phenolic resin and a curing agent was mixed with ethylene glycol as an additive to form the uniform surface. The phenolic resin was dried and cured under the environments of hot air, then converted into a glassy carbon layer by pyrolysis at 500~1,500℃. FTIR, XRD, SEM analysis, and density/porosity/contact angle measurement were performed for characterization of glassy carbon. The pyrolysis temperature for high-quality glassy carbon was optimized to be about 1,000℃. As the content of the additive increased, the effect of reducing surface defects on the coated surface, reduction of porosity, increase of contact angle, and increase of density were investigated in this study. The method of forming a glassy carbon coating layer through an additive is expected to be applicable to graphite coating and other fields.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.05a
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• pp.81-85
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• 2006

Through-the-thickness properties of thick-walled cylindrical composites are required to determine structural performances because interlaminar tensile stress is primarily responsible for structural failure of the composites during their curing process. It is necessary for evaluating the tensile properties to find individual test methods to find appropriate methods because there are no recognised international standards(test methods and test specifications) available for generating reliable tensile properties in the direction. This paper has performed an experimental Study to measure that properties of carbon fabric/phenolic composites are produced by domestic company. Several test methods using an aluminum specimen were compared and evaluated. The best method, found out, was adopted to measure transverse through-the-thickness properties of composite materials. The results show that strain trends on four faces of composite specimen are the same.

• Journal of the Korean Society of Propulsion Engineers
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• v.10 no.3
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• pp.48-52
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• 2006

Through-the-thickness properties of thick-walled cylindrical composites are required to determine structural performances because interlaminar tensile stress is primarily responsible for structural failure of the composites during their curing process. It is necessary for evaluating the tensile properties to find individual test methods to find appropriate methods because there are no recognised international standards(test methods and test specifications) available for generating reliable tensile properties in the direction. This paper has performed an experimental study to measure that properties of carbon fabric/phenolic composites which are produced by domestic company. Several test methods using an aluminum specimen were compared and evaluated. The best test method to measure transverse through-the-thickness properties of composite materials was developed by the experimental results that strain trends on all faces of composite specimen are the same.

• Journal of the Korean GEO-environmental Society
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• v.9 no.3
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• pp.45-50
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• 2008

In this work, stainless steel mesh-supported activated carbons were prepared using phenolic resin and cellulose fiber. $ZnCl_2$ was used as a activation reagent in this work. $ZnCl_2$-chemical activation method has been proposed to produce highly porous activated carbons. The objectives of this work were to develop an optimal condition for manufacturing activated carbon assemblies screen from stainless steel mesh and phenolic resin. The iodine number was more increased over activation temperature of $450^{\circ}C$. Iodine number was 657 mg/g at activation temperature of $550^{\circ}C$, penolic resin concentration 20% and $ZnCl_2$ concentration 15%. Iodine number was 1359.4 mg/g when 10% cellulose added to these conditions.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.7
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• pp.41-52
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• 2003

In this paper, three-dimensional thermo-mechanical properties of carbon-phenolic 8-hamess satin weave composites were predicted considering geometric parameters of microstructures. The effective properties were calculated by a series of numerical experiments based on unit cell analysis. The microstructural details were modeled through macro-elements, and the periodic boundary conditions were derived for corresponding un it cell types. The Monte Carlo method was employed to consider the random phase shift between the layers, and the results were investigated on the effect of the geometric parameters of shift, number of layers and waviness ratios. Experimental tests were also performed and the results were compared.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.240-246
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• 2005

Humic substances HS) from process waters at advanced water treatment plant consisted of GAC and Ozone/GAC processes were isolated and extracted by physicochemical fractionation methods to investigate their characteristics. They are characterized for their functionality, chemical composition, spectroscopic characteristics using FT-IR and $^1H$-NMR spectroscopy. Humic fraction gradually decreased from 36.3% to 24.2% from 0.45 to 0.30 mgC/L) through ozonation and carbon adsorption. The humic fraction was isolated into the phenolic and carboxylic groups using A-21 resin, and the concentration of phenolic groups gradually decreased from 38.4% to 23.5% (from 4.9 to $3.2\;{\mu}M/L$ as phenolic-OH) through ozonation and carbon adsorption. In the case of carboxylic groups, the concentration decreased from 61.6% to 43.3% (from 7.8 to $5.8\;{\mu}M/L$ as COOH) through the water treatment processes. On the other hand, concentrations of those roups decreased from 38.4% to 24.0% and 61.6% to 44.9% through carbon adsorption without ozonation, respectively. The structural changes of HS identified from FT-IR and $^1H$-NMR were consistent with the results from the isolation of functional groups in HS.