• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.11
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• pp.1249-1255
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• 2009

Cord-rubber composites widely used in tires show very complicated mechanical behavior such as nonlinearity and large deformation. Three-phase(cord, rubber and the interface) modeling has been used to analyze the stress distribution in the cord-rubber composites more accurately. In this study, finite element methods were performed using two-dimensional generalized plane strain element and plane strain element to investigate the stress distribution and effective modulus of cord-rubber composites. Neo Hookean model was used for rubber property and several interface properties were assumed for various loading directions. It was found that the interface properties affect the effective modulus and the distributions of shear stress.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.34 no.5
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• pp.583-588
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• 2010

The nonlinearity and high deformability of rubber make accurate analysis of the behavior of cord-rubber composites a challenging task. Some researchers have adopted the third phase between cord and rubber and have carried out three-phase modeling. However, it is difficult to determine the thickness and properties of the interface in cord-rubber composites. In this study, a two-dimensional finite-element method (2D FEM) is used to investigate the effective and normalized moduli of cord-rubber composites having interfaces of various thicknesses; this model takes into account the 2D generalized plane strain and a plane strain element. The neo-Hookean model is used for the properties of rubber, several interface properties are assumed and three loading directions are selected. It is found that the properties and thickness of the interface can affect the nonlinearity and the effective modulus of cord-rubber composites.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.77-89
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• 2018

In the case of fiber/rubber composites for tire applications, the interfacial adhesion between fiber and rubber significantly affects the physical properties of the finished products. Generally, organic synthetic fibers used for tire cords are treated with resorcinol formaldehyde latex(RFL) primer on the surface of the fiber to improve the adhesion to rubber. Changes of adhesion between rubber and tire cords might weaken as temperature rises due to overheating of car engine and friction with road. In this study, the effects of temperature on the primer treated polyketone cord/rubber composites and the changes in interfacial adhesion were investigated. Polyketone cord/rubber composites were prepared after RFL solution treatment on the surface of polyketone fibers. After that, composites was thermally aged at different temperature conditions(60, 80, 100, $120^{\circ}C$) and times(1, 5, 10, 15days). The adhesion strength of polyketone cord/rubber composite treated with RFL primer was higher than untreated composite by more than 3 times. After heat aging, the adhesion strength of untreated polyketone cord/rubber composites increased while the RFL treated polyketone cord/rubber composites decreased somewhat.

• Elastomers and Composites
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• v.37 no.3
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• pp.192-194
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• 2002

Polyester cord yarns have been treated in an atmospheric-pressure nitrogen plasma reactor in order to enhance their adhesion to rubber. A thin layer or the plasma was generated in the close vicinity of the yam surface using various types or surface discharge. To assess the effect of the plasma treatment on fiber surface properties, the cord thread/rubber matrix adhesion values measured using the untreated and threads cord threads were compared. The static and dynamic adhesion of the cord thread to rubber was characterized by using the standard Henley test. The dynamic adhesion values for the reference and plasma treated fiber were $7,3{\pm}1,2\;N$ and $83,5{\pm}3,5\;N$. The surface properties were investigated by scanning electron microscopy, infrared spectroscopy and electron spin resonance spectroscopy. It is concluded that both polar group interactions and increased surface area of the fibers are responsible for the improved adhesive strength.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.19 no.1
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• pp.130-135
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• 2005

The electrical fire frequently happens through careless use such as poor contact, mechanical stress on power cord sets. In this paper, we simulated a wall-model in order to investigate the patterns of fire dispersion on power cord sets which consists of vinyl cord and rubber cord, etc. The fire progress and dispersive patterns were measured by a high speed imaging system(HG-100K, REDLAKE, USA). From the results, the fire pattern of power cord sets was progressed in order of flashover, scattering and disconnection. The short-circuit of the vinyl cords happened easier than the rubber cords by the external flame. In case vinyl cord is disconnected. the fire progress is not observed because the ignition energy decreases. Whereas, the fire progressed continuously in case of the rubber cord.

• Elastomers and Composites
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• v.49 no.4
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• pp.293-304
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• 2014

Rubber air spring (RAS) is a special suspension device for the industries of automobile, railroad car and other transportation. A RAS serves as a spring component with the elastic effect of compression and expansion of air in a composite rubber bag. The main component of RAS is the rubber sleeve. Rubber sleeve is the composite which is made up of combination of chloroprene rubber (CR) and nylon 6 cord, and the adhesive strength between CR and nylon 6 cord is very important. In this study, considering the effects of additives in rubber sleeve, various physical properties were tested to find the optimal combination of composition and conditions. Further, in order to select the optimum orientation of the reinforcing fibers, numerical analysis was performed using the finite elements method. After assembling all components of RAS, it was mounted on an actual vehicle, and then it was tested air leakage, fatigue life and fundamental properties.

• Composites Research
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• v.16 no.4
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• pp.1-9
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• 2003

2 ply laminated composite is regarded to simulate the interply behavior of the belt layer of the tire. It was cone with 3 dimensional FE(Finite Element) analysis to determine interply shear stress and strain. Widthwise, the shear strain was measured by the pin method. These results are compared with those of CLT(classical lamination theory) in center region and those of Kassapoglou's and Kelsey's theory in edge region. In the FE analysis. rubber is assumed as linear elastic material. and rubber/cord laminate as the orthotropic material composed of cord and rubber In the FE result, interlaminar shear stress causing the interlaminar delamination has the largest value in the edge region of the inner rubber layer. Numerical results obtained coincides with CLT well in the center region, and agrees with other theoretical result little in the edge region.

• Journal of Adhesion and Interface
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• v.15 no.2
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• pp.49-56
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• 2014

In this study, properties of adhesion between adhesion promoter-containing rubber compound and zinc coated steel cord was investigated. Cobalt salt, resorcinol formaldehyde resin (RF resin) and hexamethoxymethylmelamine (HMMM) were used to adhesion promoter. Since cobalt salts accelerate sulphidation rate of zinc at zinc coated steel cord surface, pullout force of rubber compound applying cobalt salts was increased compared to that of rubber compound without applying cobalt salts. Pullout force and rubber coverage of rubber compounds applying all adhesion promoters were superior because strong interlocking between rubber matrix increased modulus due to applying RF resin and HMMM and grown zinc sulfides at zinc coated steel cord surface.

• Journal of the Korean Society for Railway
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• v.3 no.3
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• pp.109-116
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• 2000

An air spring which is a part of the railroad vehicle suspension system is used to reduce and absorb the vibration and the noise. Main components of the air spring are a cord reinforced rubber bellows, a upper plate, a lower plate and a stopper rubber spring. The characteristics of the air spring which are the load capacity, the vertical and the horizontal stiffness are determined by the configuration of the rubber bellows, the angle of cord, and the mechanical properties of cord. Computer simulations using a commercial finite element analysis codes are executed to predict and evaluate the load capacity and the stiffness. The appropriate shape and cord angle of the air spring are selected to meet the required specifications of the air spring. Several samples of the air spring are manufactured and experimentally evaluated. It is shown that the results by computer simulation arc in close agreement with the test results.

• Journal of Adhesion and Interface
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• v.3 no.2
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• pp.40-44
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• 2002

We invested effect of the keeping-time of uncured composite and thermal aging, of cured composite on adhesive strength for rubber-brass coated steel cord composite in this study. We also evaluated how the adhesive strength affects to tire endurance. Using PAD adhesion specimen, peel adhesive strength was measured. The uncured composite was kept for several days up to 35 days in factory. Cured composite was also kept for 5 and 10 days at $85^{\circ}C$ in dry oven. Peel adhesive strength was decreased with increasing keeping-time and showed lower value with increasing thermal aging time. The lower peel adhesive strength, the lower tire-endurance. This fact was caused by the humidity and thermal aging which affected in the decrease of adhesive strength of the rubber-steel cord composite and resulted in interface fracture between rubber and steel cord. This phenomenon was confirmed from SEM investigation and tire-endurance. It was just known that corrosion of steel cord's surface and aging of adhesive layer strongly affected to decrease of adhesive strength. This resulted in directly decreasing tire-endurance.