• Corrosion Science and Technology
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• 제13권5호
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• pp.163-169
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• 2014

The corrosion resistance of epoxy-coated carbon steel was evaluated. The carbon steel surface was subjected to different treatment methods such as steel grit blasting and power tool treatment as well as contamination of water soluble salt. To study the effect of the surface treatments and contamination, the topology of the treated surface was observed by confocal microscopy and a pull-off adhesion test was conducted. The corrosion resistance of the epoxy-coated carbon steel was further examined by electrochemical impedance spectroscopy (EIS) combined with immersion test of 3.5 wt% of NaCl solution. Consequently, the surface contamination by sodium chloride with $16mg/m^2$, $48mg/m^2$ and $96mg/m^2$ didn't affect the adhesion strength for current epoxy coated carbon steel and blister and rust were not observed on the surface of epoxy coating contaminated by various concentration of sodium chloride after 20 weeks of immersion in 3.5 wt% NaCl aqueous solutions. In addition, the results of EIS test showed that the epoxy-coated carbon steel treated with steel grit blasting and power tool showed similar corrosion protection performance and surface cleanness such as Sa 3 and Sa 2.5 didn't affect the corrosion protectiveness of epoxy coated carbon steel.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 춘계학술대회 논문집
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• pp.91-93
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• 2009

A large steel ingot needs to be larger and larger in size and an ultra high clean, no defect in quality with a low hot top ratio for the resent heavy industry. The demands are very difficult to achieve simultaneously because of their contradictive effect to each other in results. In this study, 30ton steel ingot was cast in a foundry with an optimized design parameter of cast mold and cast process conditions for the low hot top ratio, 12%. The cast ingot was analyzed in macro defect, segregations, and cleanness. No macro defect was founded in central surface of the ingot. The degree of segregation and cleanness are in the controlled range with a sound quality.

• 한국정밀공학회지
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• 제26권8호
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• pp.96-103
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• 2009

The roll forming process is commonly used for the conventional 'Fe' metal products such as a furniture drawer guide or an up-down slide guide. Recently its applications are variously expanded to the sanitary facilities or electronic devices. It is essentially required the cleanness for the high technology application and any corrosion or rust are not allowed. Therefore, in those applications the stainless steel materials are strongly demanded as the substitution of 'Fe' steel. However the mechanical properties of stainless steel are not suitable for forming process compared with those of 'Fe' steel. Up to now, the conventional F.E.M.(Finite Element Method) has been used to analyze and design the roll forming process. The purpose of this research is to obtain the proper production process and the shape of rolls to manufacture the high precision slide rails made of stainless steel material. The commercial program, SHARPE-RF, is used to analyze the entire roll forming process. The results show that the rolling process and the roll design by F.E.M. are useful from the good agreement between the shapes of products estimated by F.E.M. and those of the actual products.

• 자원리싸이클링
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• 제10권3호
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• pp.37-42
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• 2001

21세기 철강산업에 요구되는 경제성, 환경친화성, 고효율성을 동시에 만족하는 슬래그 정련조업 조건을 슬래그 엔지니어링 개념에 입각하여 평가하였다. 제선 공정의 경우, 기존의 슬래그 조성에서 염기도를 증가시킴으로써 우수한 로내 통액성 및 향상된 용선품질 확보가 가능할 것으로 평가되었으며, COREX 조업에서는 ($SiO_2$+ $A1_2$$O_3$) 농도를 소량 감소시킴으로써 보다 우수한 유동성 및 정련능 확보가 가능한 것으로 예측되었다. 한편, Stainless Steel-AOD공정의 경우, 소량의 CaO농도 증가를 통하여 현재보다 양호한 정련능 확보가 가능함을 알 수 있었으며, 슬래그 중 (CaO+$A1_2$$O_3$)농도 증가를 통해 $CaF_2$의 사용량 감소를 이룩할 수 있을 것으로 예측되었다.

• 한국전기전자재료학회논문지
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• 제29권11호
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• pp.690-695
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• 2016

Induction cooktop has a great attention due to its safety, quick heating and cleanness compared to gas oven. However, the materials for induction cookware is limited to steel or stainless-steel which has the magnetic property. Recently, it has been tried to apply various porcelain to induction cookware after printing the silver layer on the bottom of cookware plates and co-firing at high temperature. Glass frits are added in the silver paste to improve an adhesion force between porcelain materials containers and transferred silver layer. The hybrid silver pastes for induction cookware requires the proper electrical resistance and the thermal conductivity with base plates. After sintering process at $800^{\circ}C$, a part of melted glass migrated to the porcelain and the rest of the glass frit was exposed to the surface. It was confirmed that most of the glass frit formed an adhesion layer between the porcelain and transferred silver layer that enhances the adhesion force.

• 복식
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• 제50권
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• pp.129-144
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• 2000

In the history of the costume of Western Europe one of the most interesting apects is that the silhouette of women's dress has been continuously evolved. There can be various origins in this changing silhouette but the most important origin is that clothes of any period are the reflection of the architectural political religious and economic background against which they are worn they must also be djusted to the texture and design of the materials produced at the time and of course there is always the basic instinct of sex attraction. The changing line in men's and women's clothes has been demanded by each period but man's great active life did not required the development of exaggerated line which could restrict his movements. Exaggeration in men's clothes has usually been confined to accessories only details could be simplified or abandoned altogether in time of action. However Woman has no great concern in these restrivtions and when an era demanded an exaggerated silhouette she developed it to the utmost limit with out any hesitation plunged herself into whalebone cane and steel for the desired line and then later to adapt herself to a changing world just as without any hesitaion abandoned all these artificial props. In this study first of all the origin of the corset and the evolution of silhouette will be chronologically studied and rearranged on the basis of written materials such as text books theses and catalogs which are related to corset In this section the most important backgrounds-social religious and economic-which caused the chages of silhouette will be scrutinized in a time order. Then the shapes and functions of corsets will be looked into in a more detailed way. In addition the materials and decorations which were preferred to achieve the desired silhouette will be examined. Finally underwear which was and has been worn for cleanness protection the shapes of outer clothes and erotic mood will be studied.