• Composites Research
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• v.24 no.4
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• pp.1-4
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• 2011

In this work, we successfully fabricated graphene oxide (GO) and GO-based PMMA composite fiber and nylon films. Dynamic mechanical and tensile properties of PMMA-GO composite fiber showed that GO is efficient reinforcement for polymer matrices. However, Nylon 6,6-GO composite films showed low reinforcement efficiency in terms of dynamic mechanical and tensile properties due to the colloid instability of GO in formic acid at a low pH level.

• Fire Science and Engineering
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• v.33 no.3
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• pp.21-28
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• 2019

To examine the mechanical and combustion characteristics of FRTP, either polycarbonate or nylon were used as a matrix, and either glass fiber or carbon fiber were used as the fiber reinforcement. The fiber reinforcement content was differentiated at 0~40 wt%. The tensile strength and heat distortion temperature increased with increasing reinforcement content. When the fiber reinforcement content was above 30 wt%, the flammability rating showed V-0. As the fiber reinforcement content increased from 0 to 40 wt%, the peak heat release rate of polycarbonate decreased by approximately 51% and that of nylon decreased by approximately 24%. The rate of CO generation decreased for a period of time, and then increased. This appears to have resulted from incomplete combustion. The rate of CO₂ generation shows a similar tendency with the heat release rate. As fiber reinforcement content levels increased from 0 to 40 wt%, the CO₂ peak rate of polycarbonate generation decreased by approximately 50% and that of nylon decreased by 28%.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 1996.05a
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• pp.241-252
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• 1996

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.557-560
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• 2008

Fiber reinforcement has been being widely used in concrete to enhance the mechanical properties and to reduce the micro-cracking caused by plastic and drying shrinkage. While researches has been focused on the benefits of fiber reinforcement, the properties of fiber reinforced concrete are strongly dependent on the type, shape and the amount of fibers in concrete. In this study, the resistance of nylon fiber reinforced concrete against the chloride ion penetration was experimentally observed by NT Build 492. The test results showed that the addition of nylon fiber has little effect on the change of the resistivity of concrete to the chloride ion penetration.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.10
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• pp.2026-2033
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• 2002

The purpose of this study is to investigate the effect of mechanical properties of the FREI using horizontal stiffness and vertical stiffness by experiments. Two kinds of FREI are designed and fabricated. The steel plates of SREI are replaced with fibers in order to reduce the cost of fabrication and installation. At first, the Nylon fiber is adopted as feasibility study of FREI. The experimental results of Nylon FREI and SREI show that the vertical stiffness of Nylon FREI is lower than SREI, and effective damping is two times higher than SREI. Carbon is adopted, by these rusults, as strong reinforcement than Nylon and full scale of carbon FREI was designed and fabricated. By the experimental test results, it is shown that the vertical stiffness of carbon FREI is three times higher than SREI, and two times higher in effective damping. As a result, the proposed FREI can replace the SREI as a seismic isolator.

• Journal of the Korea Concrete Institute
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• v.27 no.2
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• pp.157-167
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• 2015

Cement composites subjected to high-velocity projectile shows local failure and it can be suppressed by improvement of flexural toughness with reinforcement of fiber. Therefore, researches on impact resistance performance of cement composites are in progress and a number of types of fiber reinforcement are being developed. Since bonding properties of fiber with matrix, specific surface area and numbers of fiber are different by fiber reinforcement type, mechanical properties of fiber reinforced cement composites and improvement of impact resistance performance need to be considered. In this study, improvement of flexural toughness and failure reduction effect by impact of high-velocity projectile have been evaluated according to fiber type by mixing steel fiber, polyamide, nylon and polyethylene which are have different shape and mechanical properties. As results, flexural toughness was improved by redistribution of stress and crack prevention with bridge effect of reinforced fibers, and scabbing by high-velocity impact was suppressed. Since it is possible to decrease scabbing limit thickness from impact energy, thickness can be thinner when it is applied to protection. Scabbing of steel fiber reinforced cement composites was occurred and it was observed that desquamation of partial fragment was suppressed by adhesion between fiber and matrix. Scabbing by high-velocity impact of synthetic fiber reinforced cement composites was decreased by microcrack, impact wave neutralization and energy dispersion with a large number of fibers.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.141-142
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• 2014

Decrease of performance degradation of High Strength Concrete occurs more than that of normal strength concrete at elevated temperature. Therefore, when it comes to evaluating performance of structures, strain of concrete subjected to elevated temperature and loading are important items. In this study, creep strain of High Strength Concrete sunjected to various temperature conditions and 33% loading was evaluated. As a result, creep strain increased with increase of temperature and loading. Creep strain of concrete at high temperature is influenced by loading.

• Textile Coloration and Finishing
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• v.34 no.2
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• pp.109-116
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• 2022

Tire codes are made of materials such as hemp, cotton, rayon, nylon, steel, polyester, glass, and aramid are fiber reinforcement materials that go inside rubber to increase durability, driveability, and stability of vehicle tires. The reinforcement of the tire cord may construct a composite material using tires such as automobiles, trucks, aircraft, bicycles, and fibrous materials such as electric belts and hoses as reinforcement materials. Therefore, it is essential to ensure that the adhesive force between the rubber and the reinforced fiber exhibits the desired physical properties in the rubber composite material made of a rubber matrix with reinforced fibers. This study is a study on the heat treatment conditions for improving the adhesion strength of the tire cord and the reinforced fiber for tires. The core technology of the drying process is a uniform drying technology, which has a great influence on the quality of the reinforcement. Therefore, the uniform airflow distribution is determined by the geometry and operating conditions of the dryer. Therefore, this study carried out a numerical analysis of the shape of a drying nozzle for improving the performance of hot air drying in a dryer used for drying the coated reinforced fibers. In addition, the flow characteristics were examined through numerical analysis of the study on the change in the shape of the chamber affecting drying.

• Composites Research
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• v.34 no.2
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• pp.136-142
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• 2021

3D printing technology has the advantage of easy to make various shapes of products without a mold. However, it has a problem such as mechanical properties vary greatly depending on materials and manufacturing conditions. Thus, the need for research of 3D printing technology on ways to reduce manufacturing cost compared to physical properties is increasing. In this study, a 3D printing thermoplastic structure was fabricated using short fiber carbon fiber reinforced nylon filaments. And a method of improving mechanical properties was proposed by reinforcing the outer surface using pultruded continuous fiber-type carbon fiber or glass fiber-reinforced thermosetting composite material. It was confirmed that the bending properties were improved according to the reinforcing position of the stiffener and the type of fiber in the stiffener.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.6
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• pp.92-98
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• 2019

In this study, we developed a repair material incorporating PVA powder resin and nylon fiber into cemented carbide used in the existing field to improve adhesion performance and water tightness with existing concrete. Flexural behavior evaluation was performed. The main experimental variables were PVA powder resin, nylon fiber mixing rate and damage type, and performance tests were conducted to evaluate compressive strength and flexural behavior after repairing materials. It was found that all formulations fully satisfied the required performance of the repair material. The flexural strength test results of the repaired tube specimens showed that the performance of the repaired materials was maximized when the nylon fiber was added and the PVA powder was added in an appropriate amount. The flexural behavior of all the specimens showed the flexural behavior of the structural members with a low rebar ratio, suggesting that the amount of iron wire in the domestic fume pipe was somewhat insufficient. That is, it was confirmed that the amount of reinforcement of the steel wire was somewhat small, so that the concrete was cracked before the behavior of the concrete and the steel wire reached the extreme state, and the concrete was immediately destroyed beyond the tensile strength of the concrete.