• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2001년도 춘계학술대회 발표논문집
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• pp.91-94
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• 2001

Powder Metallurgy method have been used to fabricate TiC base composite with ferrous binder. TiC base composite has versatile hardness and is usable as sintered, or after heat treatment as required by the given applications. Smooth, round TiC grains impart high wear resistance and lubricity as well known characteristics of this composite. Annealed composite can be formed by conventional machining and be hardened up to 70 H$\_$R/C in vacuum. The optimizing fabrication process enables this composite to improve mechanical properties in heat, wear and corrosion environments. This study has examine the relationship between fabrication condition and mechanical property in TiC-Cr-Mo-Fe Composite.

• International Journal of Naval Architecture and Ocean Engineering
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• 제2권1호
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• pp.45-56
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• 2010

Polymer composite materials offer high strength and stiffness to weight ratio, corrosion resistance, and total life cost reductions that appeal to the marine industry. The advantages of composite construction have led to their incorporation in U.S. yacht hull structures over 46 meters (150 feet) in length. In order to construct even larger hull structures, higher quality composites with lower cost production techniques need to be developed. In this study, the effect of composite hull fabrication processes on mechanical properties of glass fiber reinforced plastic (GFRP) composites is presented. Fabrication techniques investigated during this study are hand lay-up (HL), vacuum infusion (VI), and hybrid (HL+VI) processes. Mechanical property testing includes: tensile, compressive, and ignition loss sample analysis. Results demonstrate that the vacuum pressure implemented dining composite fabrication has an effect on mechanical properties. The VI processed GFRP yields improved mechanical properties in tension/compression strengths and tensile modulus. The hybrid GFRP composites, however, failed in a sequential manor, due to dissimilar failure modes in the HL and VI processed sides. Fractography analysis was conducted to validate the mechanical property testing results.

• 대한기계학회논문집B
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• 제32권10호
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• pp.800-809
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• 2008

Scanning Thermal Microscope (SThM) is the tool that can map out temperature or the thermal property distribution with the highest spatial resolution. Since the local temperature or the thermal property of samples is measured from the extremely small heat transferred through the nanoscale tip-sample contact, improving the sensitivity of SThM probe has always been the key issue. In this study, we develop a new design and fabrication process of SThM probe to improve the sensitivity. The fabrication process is optimized so that cantilevers and tips are made of thermally grown silicon dioxide, which has the lowest thermal conductivity among the materials used in MEMS. The new design allows much higher tip so that heat transfer through the air gap between the sample-probe is reduced further. The position of a reflector is located as far away as possible to minimize the thermal perturbation due to the laser. These full $SiO_2$ SThM probes have much higher sensitivity than that of previous ones.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1254-1258
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• 2007

Electro-active polymer (EAP), one of the smart materials, is a new alternative offering ultra-precise movements and bio-compatibility. We present the results of the design, fabrication, and performance evaluation of a fabricated diaphragm-type polymer actuator using segmented polyurethane(SPU). This paper illustrates the relationship between the elastic modulus and maximum deflection as a key property of the Maxwell stress effect and also presents the relationship between the dielectric constant and maximum deflection as a key property of the electrostriction effect, especially in polymer actuators using SPU. A diaphragm-type actuator was used to induce an equation of the vertically distributed load by using a fully clamped circular plate as the boundary condition. To verify the equation, the results were compared to the data measured from load cell. In the near future, a low-cost check valves and bio-robot can be applied by its actuators.

• 한국광학회지
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• 제11권4호
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• pp.255-260
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• 2000

유기 금속화합물을 출발물질로 이용하는 졸-겔 방법으로 균열이 없는 유기-무기 복합 실리카 박막을 제작하였으며, 코팅방법, 조성비, prebake, postbake 온도 등의 제작조건에 따른 박막의 두께 및 굴절률의 변화를 체계적으로 조사하여 재현성 있는 제작조건을 확립하였다. 특히 광개시제를 첨가하였을 때 자외선 노광량에 따른 광학적 성질변화를 세 가지 광개시제에 대하여 측정, 비교하였다. 또한 졸-겔 박막으로 다중모드 간섭을 이용한 광 파워 분배기를 제작하여 광소자로의 응용 가능성을 살펴보았다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1104-1110
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• 2003

There are many applications of nanostructures, have been suggested by lots of researchers. It is highly required to measure the properties of nano-sized materials for design and fabrication of the nanostructures. In this paper, several techniques for measuring the mechanical properties of nano-structures are presented laying emphasis on the activity of Nano Property Measurement Team in KIMM. Some advanced applications of nano-indenter are described for measuring elastic, visco-elastic, frictional and adhesive properties as well as the standard methods of it. Micro-tensile test technique with accurate in-plane strain measurement method is also presented and its role in the property measurement of nanostructures is discussed.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.110-110
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• 2017

Biological systems offer unique principles for the design and fabrication of engineering platforms (i.e., popularly known as "Biomimetics") for various applications in many fields. For example, the lotus leaves exhibit unique surfaces consisting of evenly distributed micro and nanostructures. These unique surfaces of lotus leaves have the ability of superhydrophobic property to avoid getting wet by the surrounding water (i.e., Lotus effect). Inspired by the surface topographies of lotus leaves, the artificial superhydrophobic surfaces were developed using various micro- and nanoengineering. Here, we propose new platforms that can control hydrophilic and hydrophobic property of surfaces by mimicking micro- and nanosurfaces of various natural leaves such as common camellia, hosta plantaginea, and lotus. Using capillary force lithography technology and polymers in combination with biomimetic design principle, the unique micro- and nanostructures mimicking natural surfaces of common camellia, hosta plantaginea, and lotus were designed and fabricated. We also demonstrated that the replicated polymeric surfaces had different hydrophilic and hydrophobic properties according to the mimicking the natural leaf surfaces, which could be used as a simple, but powerful methodology for design and fabrication of controlled hydrophilic and hydrophobic platforms for various applications in the field of agriculture and biological engineering.

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2004년도 추계총회 및 연구발표회 초록집
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• pp.97.2-97.2
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• 2004

• 한국세라믹학회:학술대회논문집
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• 한국세라믹학회 2003년도 추계총회 및 연구발표회 초록집
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• pp.154.1-154
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• 2003

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1230-1233
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• 2004

Ozone is useful oxidizing gas for the fabrication of oxide thin films. Accordingly researching on oxidizing gas is required. In order to obtain high quality oxide thin films, higher ozone concentration is necessary. In this paper oxidation property was evaluated relation between oxide gas pressure and inverse temperature(CuO reaction). The obtained condition was formulated by the fabrication of Cu metal thin film by co-deposition using the ion Beam Sputtering method. Because the CuO phase peak appeared at the XRD evaluation of the CuO thin film using ozone gas, this study has succeeded in the fabrication of the CuO phase at $825^{\circ}C$.