• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.733-734
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• 2006

Granulated powders, prepared from PF-5F($D_{50}=4(\mu}m$), PF-10F($D_{50}=6{\mu}m$) and PF-20F($D_{50}=10{\mu}m$) water atomized powder, were compacted, debound and sintered to evaluate the properties of sintered parts. As a result, the relative sintered density of about 97% at sintering temperature of 1423K was obtained. It can be considered that by using granulated finer particle size powder, mechanical properties of sintered parts were also improved.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.6
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• pp.561-569
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• 2000

Single phase and condensation heat transfer characteristics of ammonia in a horizontal tube have been investigated experimentally The horizontal test section is composed of smooth SUS316 tube for refrigerant flow, surrounding annulus for water flow, and temperature and Pressure measuring sensors. For single phase test, subcooled ammonia mass flux was varied from 320 to 501 kg/mrs and temperature was varied from 18 to $47^{\circ}C$. For condensation test, mass flux and saturation temperature were varied from 86 to 128 kg/$m^2$s and 34 to $47^{\circ}C$, respectively. The equations of Gnielinski Soliman et al., Traviss et at., Cavallini and Zecchin, Shah, Chen et al., Tandon et al., and Chilli and Anand were compared with the experimental data. New correlations are proposed based on the experimental results and the absolute mean deviation of the experimental data becomes 1.0% for single phase test and 4.9% for condensation test.

• Proceedings of the KIEE Conference
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• 2006.07c
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• pp.1388-1389
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• 2006

금속의 전기비저항 측정은 4단자 방법, van der Pauw 방법, Four Point Probe(FPP) 방법 등이 있으며, 이들의 정확한 측정방법을 고찰하고, 그 중 FPP 방법에 의한 비저항의 두께효과를 비교 분석하기 위하여 비자성 금속 SUS 316을 두께별로 가공한 후 실험하였다. 그 결과 4단자 및 van der Pauw 방법으로 측정된 도전율은 각각 2.273 %IACS으로 나타났으며, FPP방법으로 측정된 도전율은 probe spacing 5.0 mm, dc current 10 A에서 시료의 두께가 2 mm일 때 2.288 %IACS, 3 mm일 때 2.271 %IACS로서 상기 두 방법으로 측정한 결과와 0.5 %이내에서 일치하였으나, 시료가 5mm 및 11 mm 에서는 매우 큰 오차를 나타냈다.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.89-90
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• 2006

Austenitic stainless steel has been used as a corrosion resistance material. However, austenitic stainless steel has poor wear resistance property due to its low hardness. In this investigation, we apply powder composite process to obtain hard layer of Stainless steel. The composite material was fabricated from planetary ball milled SUS316L stainless steel powder and WC powder and then sintered by Pulsed Current Sintering (PCS) method. We also added TiC powder as a hard particle in WC layer. Evaluations of wear properties were performed by pin-on-disk wear testing machine, and a remarkable improvement in wear resistance property was obtained.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.535-536
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• 2006

4단자 방법과 van der Pauw 측정방법으로 자성금속(Fe)과 비자성금속(SUS316)에 대한 전기 비저항을 시험한 결과 van der Pauw 방법에 의한 측정결과를 기준값으로 비교하였을 때, 전극 간격이 시료 단위면적 총길이의 3배에 해당하는 위치에서 비저항 값이 일치하였으며, 이를 도전율로 환산하였을 때 전극 간격이 좁을 수 록 도전율은 크게 나타났다.

• Journal of the Korean institute of surface engineering
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• v.37 no.5
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• pp.289-295
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• 2004

A dense palladium-nikel (Pd-Ni) alloy composite membrane has been fabricated on microporous nickel support mixed with submicron/micron nickel powder instead of mesoporous stainless steel support. Plasma treatment process is introduced as pre-treatment process instead of HCI activation. Pd-Ni alloy composite membrane prepared by electro plating was fairly a uniform and dense surface morphology. The membrane was characterized by permeation experiments with hydrogen and nitrogen gases at temperature 773 K and pressure 2.2 psi. The results showed that hydrogen ($H_2$) permeance was 27 ml/$\textrm{cm}^2$ㆍatmㆍmin and hydrogen/ nitrogen ($_H2$$N_2$) selectivity was 8 at 773 K.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.251-251
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• 2012

다양한 금속기판 위에 탄소나노튜브(CNT)를 직접성장 시키는 경우, 플라즈마를 이용한 기판 전처리가 CNT의 저온 합성 및 합성수율 향상에 미치는 영향을 살펴보았다. 합성용 금속기판으로는 SUS316L, Inconel, Invar, Hastelloy 등 Ni계 합금을 이용하였다. 전처리 시 플라즈마의 인가전력 및 기판온도의 증가에 따라 기판 표면조도의 증가를 확인하였고, 그에 따른 합성온도 저하 및 합성수율 증대 결과를 얻었다. 기판 열처리를 부가적으로 실시한 경우, 기판 열처리 온도 또한 합성수율에 영향을 미침을 알 수 있었으며, 특히, 인코넬 기판의 경우, 열처리 후 플라즈마 전처리를 실시한 기판에서 합성수율이 크게 향상되는 것을 알 수 있었다.

• Journal of the Society of Naval Architects of Korea
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• v.45 no.5
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• pp.530-537
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• 2008

Austenitic stainless steels(SUS 304, SUS 316), which are used for safety control valve of LNG carrier, are occasionally exposed in the cryogenic environment. In this regards, it is required to evaluate the mechanical characteristics under the low temperature environment. In this study, a series of uniaxial tensile test was carried out varying temperature for austenitic stainless steel. The phenomena of the strain-induced plasticity have been observed on the all temperature ranges. The critical value for threshold of 2nd hardening due to the phase transformation induced plasticity as well as the increase of hardening have been reported. The summarized experimental results would be used for the validation of numerical techniques applicable for the nonlinear hardening behavior of austenitic stainless steel under the cryogenic temperature environment.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.11
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• pp.1139-1145
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• 2011

An automated anastomotic ring-pin system consisting of both the anastomotic ring-pin system and the coupler device has eliminated the drawbacks of the suture method. High density polyethylene (HDPE), a material with outstanding biocompatibility and injection molding capability, was used in the ring. SUS316 stainless steel, Ti-6Al-4Nb, Ti-6Al-4V, and unalloyed titanium were used in FEM simulations of the micropin. The authors categorized the microvascular anastomotic ring micropins into short neck (SN) and long neck (LN) groups in order to evaluate the effect of the micropin's fillet radius and neck length on the von Mises stress. The micropins were further divided into those with and without fillet. On the basis of the fillet radius rate (FRR), which represents the rate of change in the von Mises stress with respect to the availability and shape of the fillet, and the neck length rate (NLR), which represents the rate of change in the von Mises stress with respect to changes in the length of the neck within the fillet shape, it can be concluded that the SN-3 neck design is the most stable.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.4
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• pp.1-9
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• 2021

A60 class deck penetration piece is a fire-resistance apparatus installed on the deck compartment to protect lives and prevent flame diffusion in fire accidents. In case that the A60 piece is newly developed or its initial design is revised, it is important to verify the fire resistance performance using a fire test procedure (FTP) code. In this paper, transient heat transfer analysis was carried out to evaluate the fire resistance design compatibility of the newly devised A60 piece. The analysis results were verified via a fire test. The heat transfer characteristics were also investigated by comparing design specifications, such as diameter, internal configuration, and material type. The analysis was performed using ABAQUS/Implicit, and the fire test was performed according to the FTP code. The fire resistance performance of the A60 pieces satisfied the safety of life at sea convention regulation. The material type was the most important design specification for the A60 piece. Based on the maximum test temperature, the measured temperature of SUS316L material was 25% lower than that of S45C on average. The differences between thermal conductivity and specific heat of each material were 17% and 58%, respectively.