• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.10
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• pp.2044-2051
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• 2002

In this paper, the deformed shape, the contact forces and the load-displacement curves of the real hollow gasket made of silicon rubber are analyzed using a commercial finite element program MARC. In the numerical analysis, the silicon rubber is assumed to have the properties of the geometric and material nonlinearity and the incompressibility, and the hyperelastic constitutive relations of that material are represented by the generalized Mooney-Rivlin and Ogden models. The outer frictional contact between the hollow gasket and the groove of rigid container and the inner self-contact of the hollow gasket are taken into account in the course of numerical computation. Experiments are also performed to obtain the material data for numerical computation and to show the validity of the mechanical deformation of the hollow gasket, resulting in good agreements between them.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.10
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• pp.95-101
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• 2021

An analysis was conducted to predict the behavior of gasket by applying an optimal-strain energy-density function selected through a uniaxial tensile test and an analysis of the gasket used in an actual hydrogen fuel cell. Among the models compared to predict the materials' properties, the Mooney-Rivlin secondary model showed the behavior most similar to the test results. The maximum stress of the gasket was not significantly different, depending on the location. The maximum surface pressure of the gasket was higher at positions "T" and "Y" than at other positions, owing to the branch-shape effect. In the future, a jig that can measure the surface pressure will be manufactured and a comparative verification study will be conducted between the test results and the analysis results.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.6
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• pp.60-66
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• 2022

The optimal strain energy function was obtained by comparing the results of the analysis using the strain energy functions obtained by uniaxial tensile and equibiaxial tensile tests on gasket materials used in hydrogen fuel cells, with the results measured using a contact pressure measurement sensor. At this time, even when only the uniaxial tensile test was conducted, Yeoh could obtain the most accurate results even by conducting only the uniaxial tensile test. Using this, an analysis of the cross section of the gasket used in stack confirmed a safe contact pressure and no deformation on the separator. In the future, research will be conducted to verify the gasket durability by reliability evaluation.

• Journal of the Korean Vacuum Society
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• v.1 no.2
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• pp.237-243
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• 1992

Two gaskets of Al 2024-T4 and annealed al 2024-T4 were made. We had acquired 2 $\times$ 10-12torr in a chamber using them. Microstructures, hardness and stress concentration of the gaskets were examined before and after baking. Knife edge damages such as decrease of edge height(H) and increase of edge angle() were found on knife edges when the Al 2024-T4 gasket was used. But no damage was found with the annealed Al 2024 gasket.

• Communications of the Korean Mathematical Society
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• v.31 no.2
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• pp.263-275
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• 2016

Quantum graph of Sierpinski gasket type with attached leads in an electric eld is considered. We study the dependence of the transmission coecient via the wave number of the quantum particle. It has strongly resonance character. The in uence of the amplitude and the orientation of the electric eld on the coecient is investigated.

• Proceedings of the KAIS Fall Conference
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• 2011.05b
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• pp.821-823
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• 2011

본 논문에서는 초고온/고압의 환경에서 사용되는 메탈 구루부드 가스켓의 품질 및 생산성 향상 그리고 원가절감을 목표로 Gasket제작 전용기계시스템을 개발하여 제작기술혁신을 하고자 하였으며, 전용기계시스템의 구성은 그루부 가공전용기, 벤딩 전용기, 후열처리 전용기, 용접비드 황삭전용기, 용접비드 연삭전용기로 이루어져 있다.

• Proceedings of the Korean Vacuum Society Conference
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• 1992.02a
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• pp.41-41
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• 1992

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.4
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• pp.488-494
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• 2011

Gasket plays an important role on sealing of the polymer electrolyte membrane fuel cell (PEMFC) stack. Stack requires gaskets in each cell to keep the hydrogen and air/oxygen within their respective regions. The failure of the gasket creates the problems of fuel leakage, mixing, damage on parts and can be a direct reason for the degrading the efficiency of fuel cell. The purpose of this paper researches on how mechanical properties of EPDM gasket in PEMFC are changed after long-term operations. The EPDM (ethylenepropylene-diene monomer) gaskets are obtained from the stack after long-term operations. DMA (dynamic mechanical analysis) is conducted to access the change of mechanical properties of the EPDM gasket. SEM/EDS (scanning electron microscope/energy dispersive spectroscopy) was used to show the surface topography and chemical characterization on the sample surface.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.12
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• pp.54-61
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• 2018

Incomplete combustion in automotive engines is a major cause of harmful exhaust gases. In this study, to prevent incomplete combustion and reduce exhaust gas emissions, a gasket blade for increasing the air velocity was applied to the intake manifold, and the change in exhaust gas was investigated theoretically and experimentally. First, simulation analysis for flow according to the number and angle of the gasket blade was performed using a 3D flow analysis program. As an analysis result, the internal average velocity of the gasket blade was optimum at 6-blade with an angle of $30^{\circ}$. Based on the simulation results, experiments were conducted to verify the effects of the gasket blades on the exhaust gas in a non-load engine simulation system. As the engine speed was increased from 2000 to 4000 rpm, exhaust gases of HC, CO, and NOx decreased by 23.4%, 16.5%, and 3.8%, respectively, and the emission decreasing effect was reduced.

• Corrosion Science and Technology
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• v.14 no.6
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• pp.288-295
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• 2015

The present work addresses crevice and galvanic corrosion processes occurring at the cylinder head gasket/cylinder head interface and cylinder head gasket/cylinder liner interface of four-stroke medium-speed diesel engines for marine applications. The contact between these systems and the marine environment can promote formation of demanding corrosion conditions, therefore influencing the lifetime of the engine components. The electrochemical behavior of various metals and alloys used as head gasket materials (both ferrous alloys and copper alloys) was investigated. The efficacy of corrosion inhibitors was determined by comparing electrochemical behavior with and without inhibitors. In particular, crevice corrosion has been investigated by electrochemical tests using an experimental set-up developed starting from the requirements of the ASTM G-192-08, with adaptation of the test to the conditions peculiar to this application. In addition to the crevice corrosion resistance, the possible problems of galvanic coupling, as well as corrosive reactivity, were evaluated using electrochemical tests, such as potentiodynamic measurements. It was possible to quantify, in several cases, the corrosion resistance of the various coupled materials, and in particular the resistance to crevice corrosion, providing a basis for the selection of materials for this specific application.