• International Journal of Concrete Structures and Materials
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• 제4권1호
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• pp.17-23
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• 2010

The feasibility of the use of scrap tire rubber in concrete was investigated. The tests conducted in two groups: replacing of coarse aggregates with crumb rubber and cement particles with rubber powder. To distinguish the properties of new concrete, the following mechanical and durability tests were designed: compressive, tensile and flexural strength, permeability and water absorption. Rubber addition could affect the concrete properties depend on the type and percentage of the rubber added. Although the rubber addition modifies the mechanical characteristics of concrete in a way, but higher rubber content could not be useful. Concrete durability showed more dependency to the type of rubber instead of percentage of rubber. Moreover, to optimize the mechanical and durability of rubberized concrete, the useful percentage of rubber has been recommended.

• Elastomers and Composites
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• 제47권3호
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• pp.194-200
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• 2012

고무재료는 배합조건에 따라 기계적 거동이 다르기 때문에 피로수명평가를 위해 부품소재에 대한 물성데이터 확보가 선행되어야 한다. 그러나 모든 종류의 배합조건을 고려하여 표준화된 재료물성을 확보하는 것은 현실적으로 불가능하다. 따라서 본 연구에서는 최소한의 제한된 실험으로부터 피로수명평가를 위한 입력물성을 선택하기 위한 방법을 제시하였으며, 피로수명 평가를 위한 최적 피로손상 파라미터를 결정하였다. 이러한 결과를 활용하여 부품의 피로수명 평가결과와 내구시험결과를 비교한 후, 본 연구에서 제안된 피로수명 평가절차의 타당성을 검토하였다.

• 대한조선학회논문집
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• 제59권3호
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• pp.157-163
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• 2022

An automatic mooring system for a ship consists of a vacuum suction pad and a mechanical part, enabling quick and safe mooring of a ship. In the development of a mooring system, the design of a vacuum suction pad is a key to secure enough mooring forces and achieve stable operation of a mooring system. In the vacuum suction pad, properly designing its rubber seal determines the performance of the suction pad. Therefore, it is necessary to appropriately design the rubber seal for maintaining a high-vacuum condition inside the pad as well as achieving its mechanical robustness for long-time use. Finite element analysis for the design of the rubber seal requires the use of an appropriate strain energy function model to accurately simulate mechanical behavior of the rubber seal material. In this study, we conducted simple uniaxial tensile testing of Chloroprene Rubber (CR) to explore the strain energy function model best-fitted to its experimentally measured engineering strain-stress curves depending on various temperature environments. This study elucidates the temperature-dependent mechanical behaviors of CR and will be foundational to design rubber seal for an automatic mooring system under various temperature conditions.

• 한국산업융합학회 논문집
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• 제20권3호
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• pp.221-232
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• 2017

In this study, bipolar plates in fuel cells are formed using rubber forming process. The effects of important parameters in rubber forming such as hardness and thickness of rubber pad, speed and pressure of punch that compress blank, and physical property of materials on the channel depth were analyzed. In the soft material sheet Al1050, deeper channels are formed than in materials STS304 and Ti-G5. Formed channel depth was increased when hardness of rubber pad was lower, thickness of rubber pad was high, and speed and pressure of punch were high. It was found the deepest channel was achieved when forming process condition was set with punch speed and pressure at 30 mm/s and 55 MPa, respectively using rubber pad having hardness Shore A 20 and thickness 60 mm. The channel depths of bipolar plates formed with Al1050, STS304 and Ti-G5 under the above process condition were 0.453, 0.307, and 0.270 mm, respectively. There were no defects such as wrinkle, distortion, and crack found from formed bipolar plates.

• 한국자동차공학회논문집
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• 제13권6호
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• pp.56-62
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• 2005

The fatigue analysis and lifetime evaluation are very important in design procedure to assure the safety and reliability of the rubber components. Fatigue lifetime prediction methodology of the rubber component was proposed by incorporating the finite element analysis and fatigue damage parameter from fatigue test. Finite element analysis of 3D dumbbell specimen and rubber component were performed based on a hyper-elastic material model determined from material test. The Green-Lagrange strain at the critical location determined from the FEM was used for evaluating the fatigue damaged parameter of the natural rubber. Fatigue life of the rubber component are predicted by using the fatigue damage parameter at the critical location. Predicted fatigue lifes of the rubber component agreed fairly well the experimental fatigue lives.

• Elastomers and Composites
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• 제54권1호
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• pp.70-76
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• 2019

The function and purpose of the marine rubber fender, to prevent the damage of the ship and the mooring while the ship is being attached to the pier. However, maintenance of the fender after installation is not enough, because it is generally handled as an attachment facility. Estimation the life of a marine rubber fender is important in the maintenance of a port. When manufacturers design and produce marine rubber fenders, they do so according to various conditions such as the reaction force acting on the hull and docking vessel and deformation after absorbing the kinetic energy of the ship. In this study, a method for predicting and evaluating service life from the product design and development stage was established, in order to evaluate the durability of the marine rubber fenders. The SSp-300H and HSP-300H models were used to predict the service life. The method developed in this study, is expected to predict the service life of the marine rubber fender accurately and in a comparatively shorter time, thereby contributing to the evaluation standard and quality stability of the product.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2001년도 추계학술발표대회 논문집
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• pp.121-124
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• 2001

Surface-modified silica holds considerable promise in the development of advanced materials for good mechanical properties and stability. In this work, the surface and mechanical interfacial properties of silicas treated with silane coupling agents, such as Y-methacryloxy propyl trimethoxy silane (MPS). Y-glycidoxy propyl trimethoxy silane (GPS), and Y-mercapto propyl trimethoxy silane (MCPS), are investigated. The effect of silane surface treatments of silica on the surface properties and surface energetics are studied in terms of surface functional values and contact angle measurements. And their mechanical interfacial properties of the silica/rubber composites are studied by the composite tearing energy ($G_{IIIC}$). As a result. the mechanical interfacial properties are improved in the case of silane-treated composites compared with untreated one. It reveals that the functional groups on silica surface by silane surface treatments play an important role in improving the degree of adhesion at interfaces in a silica-filled rubber system.

• Elastomers and Composites
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• 제48권1호
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• pp.67-75
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• 2013

E-TPE(Engineering Thermoplastic Polyether Ester)는 Ester 관능기를 갖는 Elastomer 소재로서 리사이클이 가능하며 빠른 가공성을 지닌다. 또한 경량성이 뛰어나 자동차의 경우 연비향상에 도움을 주는 친환경 소재로 부각되고 있다. 고무와 엔지니어링 플라스틱의 특성을 모두 가지고 있는 E-TPE는 사용 가능한 온도영역이 넓고, 내열성 및 내유성이 우수하여 자동차 부품소재분나 전기전자분야의 신소재로 주목받고 있으나 국내에서는 원천기술이 부족하여 전량 수입에 의존하고 있는 실정이므로 연구개발이 시급하다. 본 연구에서는 하드 세그먼트로 폴리에스터계(TPEE)를 base로 하여 소프트 세그먼트로 Ethylen-prophylene-Copolymer와 CSM(Choloro sulphonated polyethylene Rubber), VAMAC(Ethylene Acrylic Rubber), NBR(Acrylonitrin Butadiene Rubber)의 탄성체를 1,3-Phenylene-bisoxazoline 가교제로 동적가교 시켜 함량과 첨가된 고무에 따른 물성을 관찰하였다. 그 결과 NBR 첨가된 동적가교물의 물성이 다른 고무에 비해 내열성 및 내유성 향상에 되었음을 확인하였다.

• Elastomers and Composites
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• 제44권2호
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• pp.122-133
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• 2009

고무는 천연 고무를 비롯하여 부타디엔 고무, 스티렌-부타디엔 고무, 니트릴-부타디엔 고무, EPDM, 염소화 고무 등 산업적 요구에 따라 발전하여 왔다. 광범위한 분야에서 고무가 사용됨에 따라 새로운 물성을 갖는 합성 고무나 개질 고무의 생산이 필요하게 되었다. 본 리뷰 논문에서는 이중 결합을 포함하는 고무의 화학적 개질을 통하여 고무의 구조를 변화시키거나, 관능기, 이종 고분자 등을 도입하는 몇 가지 방법들에 대하여 정리해 보고자 한다. 특히, 최근에 많은 응용이 시도되고 있는 리빙 라디칼 중합법에 의한 고무의 개질을 소개하고 이의 효과를 알아보고자 한다.

• Elastomers and Composites
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• 제40권2호
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• pp.83-92
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• 2005

국제 환경규제에 적합한 자동차용 연료 호스를 개발하기 위하여, 배합조건을 달리한 FKM 고무재료를 내층재료로 하였을 경우, 기본물성을 비롯한 내열성, 내유성, 내연료성 및 투과성을 측정하고 연료 호스재료로서의 적합성을 조사하였다. 불소 함량이 증가함에 따라 불소 고무재료는 기본물성, 내열성, 내유성 및 내연료성의 증가를 보였으며, 66%, 69%, 71% FKM 혼합물에서 카본의 양을 20 phr로 하였을 때 연료 호스의 규격을 만족하는 것으로 나타났다. 이소옥탄과 톨루엔 그리고 가솔린과 메탄올을 혼합한 연료유로써 측정한 NBR 고무와 FKM 고무의 투과성에서 FKM 고무의 경우, 불소의 함량에 따라서 미세한 투과량의 차가 나타났으나 NBR 고무보다는 투과성이 매우 우수하였다. 또한 연료유의 성분비를 달리했을 때도 FKM 고무의 투과성에는 거의 영향이 없었으며, 투과성 실험을 거친 69% FKM 고무재료의 열적 특성에도 변화가 없었다.