• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.1
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• pp.9-15
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• 2004

Micro inorganic solids and dissolved materials contained in the white water of linerboard process was obtained by centrifugation, and their characteristics were analyzed along with their effects on the mechanical properties of linerboard. Micro inorganic materials had little influence on tensile index and ZDT of UKP sheets. They showed rather a positive effect on mechanical properties of KOCC sheets due to adsorbed polymer. Mechanical properties of KOCC sheets decreased remarkably when the concentration of dissolved materials increased especially above 4000 ppm.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.788-791
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• 2008

ZnO nanoparticle was successfully prepared by microwave irradiation method in various oxygen/nitrogen ratio atmospheres. The product prepared in a low oxygen ratio atmosphere showed tetra pod shape with high aspect ratio, c/a. PL spectra of the products showed higher UV emission intensity than the others when it was prepared in the atmosphere oxygen/nitrogen=40/60.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.10a
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• pp.211-216
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• 2003

Coated bars are protecting reinforcing bars from corrosion and enhancing durabilities of reinforced concrete structures are tested to evaluate corrosion protection properties. Tests are performed based on the relevant standards of ACI and ASTM, such as chemical resistance, salt water spray, salt crack test and chloride permeability test with the main variable of the coating thickness. Three type materials are tested by Polyethylene, epoxy and bare bar. Test results show good chemical protection property and chloride permeability. Polyethylene coated bar is good coating material than any other materials.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2004.11a
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• pp.49-49
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• 2004

• Bulletin of the Korean Chemical Society
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• v.29 no.7
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• pp.1412-1414
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• 2008

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2010.03a
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• pp.135-136
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• 2010

• Korean Journal of Materials Research
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• v.25 no.9
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• pp.442-449
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• 2015

The effects of coating parameters were investigated in wear resistance coatings of Diamalloy-406 on Inconel 718 to obtain an optimum coating condition by high velocity oxy-fuel spraying. The coating parameters, the flow rates of source gases (hydrogen and oxygen), the powder feed rate, and the spray distance, were designed by the Taguchi method. The optimal conditions were determined: oxygen flow rate 34 FRM, hydrogen flow rate 57 FRM, powder feed rate 35 g/min, and spray distance 7 inch. Friction coefficients of the coating and the substrate decreased with an increasing sliding surface temperature from $25^{\circ}C$ to $450^{\circ}C$. The friction coefficient of Diamalloy-4006 coating decreased as the sliding surface temperature increased from $0.43{\pm}0.01$ at $25^{\circ}C$ to $0.29{\pm}0.01$ at $450^{\circ}C$. The wear trace and wear depth of the coating were smaller than the substrate at all temperatures tested. The relationship between spray parameters and wear resistance was discussed extensively, based on the measured roughness, hardness, and porosity in each coating.

• Applied Chemistry for Engineering
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• v.27 no.3
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• pp.252-258
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• 2016

The weight reduction and improved mechanical property are one of the prime factors to develop new materials for the aerospace industry. Composite materials have thus become the most attractive candidate for aircraft and other means of transportations due to their excellent property and light weight. In particular, fiber reinforced polymer (FRP) composite materials have been used as an alternative to metals in the aircraft. The composite materials have shown improved properties compared to those of metal and polymeric materials, which made the composites being used as the skin structure of the airplane. This review introduces different types of materials which have been developed from the FRP composite material and also one of the most advantageous ways to employ the composites in aircraft.

• Corrosion Science and Technology
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• v.21 no.3
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• pp.230-241
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• 2022

Austenitic stainless steel has been widely used because of its good corrosion resistance and mechanical properties. However, intergranular corrosion can occur if the alloy is welded or aged. The objective of this study was to determine intergranular corrosion behaviors of austenitic medium carbon (0.05 wt%) and low carbon (0.02 wt%) stainless steel aged at several conditions. Alloys were evaluated according to ASTM A262 Practice A, ISO 12732 DL-EPR (double loop-electrochemical potentiokinetic reactivation) test, and ASTM A262 Practice C. The degree of sensitization and intergranular corrosion rate were obtained. The relationship between the degree of sensitization and the intergranular corrosion rate showed a very large fluctuation. Such behavior might be related to whether two-dimension tests or three-dimension tests were performed. On the other hand, regardless of carbon content of alloys, when the intergranular corrosion rate increased, the degree of sensitization also increased. However, the DL-EPR test showed a higher sensitivity than the Huey test for differentiating the intergranular corrosion property at a low intergranular corrosion rate, while the Huey test had a higher sensitivity than the DL-EPR test for distinguishing the intergranular corrosion property at a high intergranular corrosion rate.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.22 no.5
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• pp.254-259
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• 2012

The mechanical property enhancement was studied using fly ash produced from fluidized bed type boiler in power plant, which contains a lot of Ca component being used to carbonate for $CO_2$ fixation in the lightweight aggregates made of cement and some portion of fly ash as a cement substitution under the supercritical condition. Specimens having various fly ash substitution rates and curing periods were carbonated under the supercritical condition at $40^{\circ}C$. The weight change rate, carbonation rate by TG/DTA analysis, 1% Phenolphthalein test, specific gravity and mechanical compression strength test were performed to observe the mechanical property enhancement of the cemented materials after carbonation under the supercritical condition and to make sure those could be classified as lightweight aggregates having specific gravity under 2.0.