• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2002년도 봄 학술발표회 논문집
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• pp.311-316
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• 2002

The following results are achieved from a mortar flow test depending on stainless steel slag fineness, rate of replacement, and a research on material age compressive strength, strength activity index. 1. Flow is proportional to the stainless steel slag fineness. 2. Mixing stainless steel slag decreases compressive strength 3. Material age compressive strength has the maximum value when stainless steel slag fineness is 6000$cm^2$/g. 4. Material age 7day strength activity index satisfies KSCE 95-01 at all conditions except the case of fineness 8000$cm^2$/gㆍstainless steel slag rate of replacement 30%. 5. Material age 28day strength activity index satisfies KSCE 95-01 in case of stainless steel slag fineness 4000$cm^2$/gㆍrate of replacement 10%, fineness 6000$cm^2$/gㆍ10%, or 20%.

• Steel and Composite Structures
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• 제10권6호
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• pp.517-539
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• 2010

This paper presents the axial compressive behaviour of stub concrete-filled columns with elliptical stainless steel and carbon steel hollow sections. The finite element method developed via ABAQUS/Standard solver was used to carry out the simulations. The accuracy of the FE modelling and the proposed confined concrete stress-strain model were verified against experimental results. A parametric study on stub concrete-filled columns with various elliptical hollow sections made with stainless steel and carbon steel was conducted. The comparisons and analyses presented in this paper outline the effect of hollow sectional configurations to the axial compressive behaviour of elliptical concrete-filled steel tubular columns, especially the merits of using stainless steel hollow sections is highlighted.

• 대한조선학회지
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• 제8권2호
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• pp.13-24
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• 1971

When friction welded material is actually used for parts of a machine, its fatigue strength is an important problem. Especially, there is no report which deals with mechanical properties of friction welded mild steel(S20C) and stainless steel(SUS27B). In this study are compared the compared the characteristics of such specimens as mild steel, stainless steel and welded material in the S-N diagram. And metallurgical consideration is directed to HAZ. The obtained results in these studies are summarized as follows; 1) The fatigue strength of welded material is slightly less than those of mild steel and stainless steel. 2) In the S-N diagram the knuckle point of welded material has larger number of cycle than that of stainless steel. 3) The fatigue notch factor of welded material is between those of mild steel and stainless steel. 4) mHv is the largest on the weld interface. It is larger before than after fatigue test on the stainless steel side. On the mild steel side it is the way around.

• 대한소아치과학회지
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• 제27권1호
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• pp.98-102
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• 2000

이소맹출이란 영구치열의 발육 과정중에 국소적 맹출장애로 인하여 정상적 위치에서 벗어난 치아의 맹출을 말한다. 일반적으로 이소맹출은 $2\sim6%$정도의 이환율을 보이고, 제1대구치에서 호발하며 주로 상악에서 많이 나타나고 하악에서는 드물다. 이소맹출의 원인은 국소적 원인으로 부적절한 치열궁 길이, 상악 후방부의 성장 부족, 제1대구치의 근심 맹출, 비정상적으로 큰 제 1대구치 등이 있고, 유전적인 원민으로 나타날 수도 있으며, 부적절하게 형성된 stainless steel crown에 의해서도 유발될 수 있다. 이소맹출된 치아중 66%는 가역성이므로 $3\sim6$개월 정도의 관찰 기간이 요구된다고 하였으며, 비가역성 이소맹출인 경우에는 brass wire나 elastic separator를 이용한 비교적 간단한 치료 방법, 제2유구치의 distal discing, Humphrey appliance 등과 같이 제2유구치를 유지하면서 치료하는 방법 및 제2유구치 발거후 가철식 장치나 cervical traction headgear를 이용하는 방법 등이 소개되고 있다. 본 증례는 연세대학교 치과대학병원 소아치과에 내원한 7세된 남환아로 구강 검사 및 방사선 사진 검사 결과, 4년전 개인 치과의원에서 수복된 우측 하악 제2유구치의 stainless steel crown에 우측 하악 제 1대구치가 고착되어 근심으로 심하게 경사된 양상을 보였다 원인이 stainless steel crown을 제거하고, Humphrey appliance를 제작하여 장착하였으며, 약 10주 후에 고착 상태가 해소되었다. 본 증례에서와 같이 이소맹출은 부적절하게 형성된 stainless steel crown에 의해 일어날 수 있으므로, stainless steel crown의 수복 치료에 있어서, 적절한 크기의 선택, trimming 및 contouring 등이 매우 중요하다.

• Steel and Composite Structures
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• 제30권6호
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• pp.551-565
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• 2019

A total of 36 carbon steel and stainless steel bolted connections subjected to shear loading at different strain rates was experimentally investigated. The connection specimens were fabricated from carbon steel grades 1.20 mm G500 and 1.90 mm G450, as well as cold-formed stainless steel types EN 1.4301 and EN 1.4162 with nominal thickness 1.50 mm. The connection tests were conducted by displacement control test method. The strain rates of 10 mm/min and 20 mm/min were used. Structural behaviour of the connection specimens tested at different strain rates was investigated in terms of ultimate load, elongation corresponding to ultimate load and failure mode. Generally, it is shown that the higher strain rate on the bolted connection specimens, the higher ultimate load was obtained. The ultimate loads were averagely 2-6% higher, while the corresponding elongations were averagely 8-9% higher for the test results obtained from the strain rate of 20 mm/min compared with those obtained from the lower strain rates (1.0 mm/min for carbon steel and 1.5 mm/min for stainless steel). The connection specimens were generally failed in plate bearing of the carbon steel and stainless steel. It is shown that increasing the strain rate up to 20 mm/min generally has no effect on the bearing failure mode of the carbon steel and stainless steel bolted connections. The test strengths and failure modes were compared with the results predicted by the bolted connection design rules in international design specifications, including the Australian/New Zealand Standard (AS/NZS4600 2018), Eurocode 3 - Part 1.3 (EC3-1.3 2006) and North American Specification (AISI S100 2016) for cold-formed carbon steel structures as well as the American Specification (ASCE 2002), AS/NZS4673 (2001) and Eurocode 3 - Part 1.4 (EC3-1.4 2015) for stainless steel structures. It is shown that the AS/NZS4600 (2018), EC3-1.3 (2006) and AISI S100 (2016) generally provide conservative predictions for the carbon steel bolted connections. Both the ASCE (2002) and the EC3-1.4 (2015) provide conservative predictions for the stainless steel bolted connections. The EC3-1.3 (2006) generally provided more accurate predictions of failure mode for carbon steel bolted connections than the AS/NZS4600 (2018) and the AISI S100 (2016). The failure modes of stainless steel bolted connections predicted by the EC3-1.4 (2015) are more consistent with the test results compared with those predicted by the ASCE (2002).

• Steel and Composite Structures
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• 제6권4호
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• pp.285-302
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• 2006

This paper describes the design and behaviour of cold-formed stainless steel slender circular hollow section columns. The columns were compressed between fixed ends at different column lengths. The investigation focused on large diameter-to-plate thickness (D/t) ratio ranged from 100 to 200. An accurate finite element model has been developed. The initial local and overall geometric imperfections have been included in the finite element model. The material nonlinearity of the cold-formed stainless steel sections was incorporated in the model. The column strengths, load-shortening curves as well as failure modes were predicted using the finite element model. The nonlinear finite element model was verified against test results. An extensive parametric study was carried out to study the effects of cross-section geometries on the strength and behaviour of stainless steel slender circular hollow section columns with large D/t ratio. The column strengths predicted from the parametric study were compared with the design strengths calculated using the American Specification, Australian/New Zealand Standard and European Code for cold-formed stainless steel structures. It is shown that the design strengths obtained using the Australian/New Zealand and European specifications are generally unconservative for the cold-formed stainless steel slender circular hollow section columns, while the American Specification is generally quite conservative. Therefore, design equation was proposed in this study.

• 한국정밀공학회지
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• 제16권2호통권95호
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• pp.82-86
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• 1999

An experimental study has been carried out to reduce bending load, surface roughness and springback in bending process of stainless steel sheets. A U-bending test has been performed to investigate appropriate process parameters for getting better surfaces and accurate dimensions of stainless steel products. In the test, selected process parameters are die material, lubricant, and die clearance. Die materials used in the test are STD11(HRC60), STD11(TiCN), and AMPCO. From the test results, we can suggest that AMPCO dies are most suitable for reducing bending load and surface roughness of stainless steel sheets. And STD11 dies are favorable for avoiding spring-back in the stainless steel sheet-bending.

• Journal of Welding and Joining
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• 제19권5호
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• pp.534-539
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• 2001

The formation mechanism of microconstituents in brazed joints of duplex stainless steel and Cr-Cu alloy which is an essential process of rocket engine manufacturing was investigated using Cu base insert metal. $SUS329J_3L$ and C18200 were used for base metal and AMS 4764 was used for insert metal. The brazing was carried out under various conditions. There were various phases in the joints, because of reaction between liquid insert metal and base metals. Since liquid insert metal reacts with duplex stainless steel, liquid Cu from insert metal infiltrated into the $\alpha/\beta$ interface of duplex stainless steel. Through the process of Cu infiltration, isolated stainless steel pieces come into the liquid insert metal. Since liquid insert metal reacts with Cr-Cu alloy. Cr precipitates from C18200 come into the liquid insert metal. With increment of bonding temperature and holding time, amounts and sizes of phases increased. but Cr-Mn compounds decreased at 1303k for 1.2ks and Mn-rich phases disappeared Fe-Cr compounds formed.

• 한국재료학회지
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• 제25권12호
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• pp.666-671
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• 2015

In this study, we investigated the effect of the residual carbides and tempered carbides precipitated by tempering treatment after quenching on the pitting corrosion of mod. 440A martensitic stainless steel. In quenched specimens and tempered specimens after quenching of mod. 440A martensitic stainless steel, the volume fraction of the residual carbides and total carbides decreased with the increase of the austenitizing temperature. Pitting resistance increased with the increase of austenitizing temperature. With the increase of the volume fraction of the residual and total carbides, the pitting resistance of mod. 440A martensitic stainless steel was decreased. The pitting resistance of mod. 0.5C-17Cr-0.5Ni 440A martensitic stainless steel had stronger affected by residual carbides than precipitated carbides produced by tempering.

• Journal of Welding and Joining
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• 제7권3호
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• pp.36-43
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• 1989

The furnace brazing in a Ar of copper to martensitic stainless steel(13.5Cr) using Cu-(5~8%)P-(0~8%)Sn powders was investigated. Shear strength, wettability, reacted layer, defect ratio at the stainless steel interface was evaluated. As Sn was added to the Cu-P powders, defect ratio and P content at the stainless steel interface decreased. And also as Sn was added, defect form at the stainless steel interface changed from the continuous layer to the discrete type, and shear strength of the brazed joint increased.