• 대한치과교정학회지
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• 제28권3호
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• pp.371-377
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• 1998

TiN 피막처리된 Elgiloy (Co-Cr계 선재)의 임상 적용을 검토하기 위하여 제조된 상태의 Elgiloy, $250^{\circ}C$에서 30분간 가열처리된 Elgiloy, TiN 피막처리된 Elgiloy 각각의 4가지 temper, 그리고 비교를 위하여 스테인레스강 선재의 인장 강도와 경도를 측정한 결과 다음과 같은 결론을 얻었다. $\cdot$인장강도는 모든 temper에서 TiN 피막처리된 군이 가장 높았고, 가열처리된 군, 제조상태의 군의 순으로 나타났으나 가열처리된 군과 제조상태의 군간에는 통계학적으로 유의한 차가 없었다(p>0.05). $\cdot$인장강도는 각 temper에서 TiN 피막처리시 제조상태의 Elgiloy보다 약 $10kgf/mm^2$정도의 증가를 보였다. $\cdot$경도값은 Yellow, Green, 그리고 Red temper에서는 TiN 피막처리된 군이 가장 높았고, 가열처리된 군, 제조상태의 군의 순으로 나타났으나(p<0.05), Blue temper에서는 가열처리된 군과 제조상태의 군간에 통계학적으로 유의한 차가 없었다(p>0.05). $\cdot$경도값은 각 temper에서 TiN 피막처리시 제조상태 Elgiloy보다 약 $50\~90VHN$ 정도의 증가를 보였다. $\cdot$스테인레스강의 선재와 비교할 때 제조상태에서는 Red temper와, TiN 피막처리한 경우는 Green temper와 비슷한 인장강도를 나타내었다.

• 한국철학논집
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• 제35호
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• pp.7-42
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• 2012

호락논쟁의 핵심 쟁점은 '담연허명(湛然虛明)한 심(心)'과 '청탁수박(淸濁粹駁)이 뒤섞인 기질(氣質)'의 관계를 어떻게 설명하느냐 하는 것이었다. 호론(湖論)에서는 기질(氣質)을 '심(心)의 재질(才質)'로 보아 심(心)과 기질(氣質)을 동위(同位)로 규정했으며, 낙론(洛論)에서는 기질(氣質)을 '이목구비(耳目口鼻)의 형기(形氣)'로 보아 심(心)과 기질(氣質)을 이위(異位)로 규정한 것이다. 그런데 낙론(洛論)의 이위론(異位論)은 이심이성론(二心二性論)에 빠짐은 물론, 성리학의 전반적 체계와도 크게 어긋나는 것이다. 그렇다면 우리는 호론(湖論)의 주장처럼 심(心)과 기질(氣質)을 동위(同位)로 이해해야 할 것이다. 문제는 호론(湖論)이 심(心)과 기질(氣質)을 동위(同位)로 규정하는 데 그치지 않고 동시(同時)로 규정했다는 점이다. 호론(湖論)의 주장처럼 심(心)(담연허명(湛然虛明))과 기질(氣質)(청탁수박(淸濁粹駁))을 동위동시(同位同時)로 규정하면, 인간의 심(心) 성(性)에서 '순선(純善)의 가능근거'를 확보하기 어려운바, 그리하여 낙론(洛論)에서는 호론(湖論)에 대해 "순자(荀子)의 성악설(性惡說)이나 양웅(揚雄)의 성선악혼설(性善惡混說)과 같다"고 비판했던 것이다. 한말(韓末)의 유학자 성암(醒菴) 이철영(李喆榮)은 '담연허명한 심(心)'과 '청탁수박이 뒤섞인 기질(氣質)'의 관계, 즉 '중저미발(中底未發)'과 '부중저미발(不中底未發)'의 관계를 '동위이시(同位異時)'로 규정했는바, 동위이시론(同位異時論)이야말로 심(心)과 기질(氣質)의 관계에 대한 정확한 해명이었던 것이다.

• Journal of Mechanical Science and Technology
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• 제16권10호
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• pp.1296-1302
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• 2002

A mathematical model for cold rolling and temper rolling process of thin steel strip has been developed using the influence function method. By solving the equations describing roll gap phenomena in a unique procedure and considering more influence factors, the model offers significant improvements in accuracy, robustness and generality of the solution for the thin strip cold and temper rolling conditions. The relationship between the shape of the roll profile and the roll force is also discussed. Calculation results show that any change increasing the roll force may result in or enlarge the central flat region in the deformation zone. Applied to the temper rolling process, the model can well predict not only the rolling load but also the large forward slip. Therefore, the measured forward slip, together with the measured roll force, was used to calibrate the model. The model was installed in tile setup computer of a temper rolling mill to make parallel setup calculations. The calculation results show good agreement with the measured data and the validity and precision of the model are proven.

• 대한기계학회논문집
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• 제19권2호
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• pp.408-417
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• 1995

A study on the surface roughness variation of work roll and strip at the temper rolling was performed. The results were obtained with changes according to the surface roughness of work roll and method to make the peak count on the roll in the temper rolling, and factors to affect to the work roll surface in actual rolling machine (ie. Temper mill). The results suggests that the electro-discharge textured roll has mere uniform roughness distribution than shot blasted roll and its life time is two times longer than shot blasted because it has more sine wave roughness, and it is possible to control the Rmax. In shot blasting method, Surface roughness is related to the impeller speed, But it can't control the peak count.

• Journal of Mechanical Science and Technology
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• 제15권2호
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• pp.225-231
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• 2001

A mathematical model for the analysis of roll gap phenomena in the strip temper rolling process is described. A new approach to solve the roll indentation and diverging problem in modeling of severe temper rolling cases is obtained by adopting the preliminary displacement principle of two contacted rough bodies to describe the friction behavior in the roll gap. The mechanical peculiarities of the temper rolling process, such as a high friction value with high roughness rolls and a non-circular contact arc, low reduction and non-negligible entry and exit elastic zones as well as central preliminary displacement zone etc., are all taken into account. The deformation of work rolls is calculated with the influence function method and an arbitrary contact are shape is permitted. The strip deformation is modeled by the slab method and the entry and exit elastic deformation zones are included. The preliminary displacement principle is used to determine the boundaries and to calculate the friction of the central preliminary displacement zone. The model is calibrated against the production mill data and installed in the setup computer of a temper rolling mill in POSCO. The validity and precision of the model have been proven through a comparison of the measured roll forces and the predicted ones.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 1992년도 특별강연 및 춘계학술발표 개요집
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• pp.45-47
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• 1992

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1993년도 추계학술대회 논문집
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• pp.505-511
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• 1993

The results were obtained with changes according to the surface roughness of work roll and method to make the peak count on the roll in the temper rolling, and factors to affect to the work roll surface in actual rolling machine(ie. Temper mill). Conclusions are as follows. 1. E.D.T(Electro-discharge texturing)roll is more uniform roughness distribution than shot blasted roll and it's life time is two timees longer than that of shot blasted because it has more sine wave roughness. 2. The higher peak count of surface roughness, the more time is necessary to work roll texturing In shot blasting method, Surface roughness is relating to the grit size,impeller speed and hardness of roll material, But is can't control the peak count. 3. In shot blast texturing, Surface roughness of temper rolled strip which is transfered surface roughness of work roll is more ununiform than that of E.D.T roll 4. E.D.T roll has more uniform than the shot blasted roll and has more peak count than that of shot blasted roll. The surface of painted strip to image clarity is superior to that of shot blasted roll because E.D.T roll has more peak count and smooth surface.

• KSTLE International Journal
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• 제2권1호
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• pp.80-84
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• 2001

The purpose of this paper is to show the result from the study to improve the formability and appearance which is important in the cold rolled strip, the coated strip and prepainted strip. Furthermore, to give appropriate surface roughness, shape of work roll for temper mill is also important. The strip has a greater peak counts and homogeneous roughness. This makes the prepainted surface smooth and consistent in appearance with good image clarity. Therefore, the surface roughness of the work roll is very important. The reason that surface roughness of the work roll is transferred to the strip surface is the rolling farce and tension at the temper rolling or cold rolling. This study is classified in order to get an accurate and homogeneous roughness. There are few papers published in this field, because its importance is not known and the proper operation of the machine is not generally well known. This paper investigates the correlation between strip surface roughness and the surface of the work roll. After studying the surface roughness and shape according to the texturing method for roll surfaces at temper rolling, the findings were as follows. Irregular surface roughness can be compensated with several paint coatings, but this also makes the quality deteriorate and manufacturing costs go up.

• 열처리공학회지
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• 제34권1호
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• pp.1-9
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• 2021

The martensitic stainless steel has excellent corrosion resistance and higher strength by quenching and tempering heat treatment. It has been widely used as blade material due to these properties. The hardness and impact toughness of martensitic stainless steel depended strongly on tempering temperatures. The 12Cr martensite stainless steel (SS 410) tempered about 540℃ showed temper embrittlement. To know cause of temper embrittlement in terms of phase identification, a detailed analysis of electron diffraction patterns during TEM observations has been carried out on the <110>α-Fe and <113>α-Fe zone axes for temper embrittlement specimen. The double electron diffraction spots at 1/3(211) and 2/3(211) positions were observed. The lattice space between individual diffraction spots was about 3.5 Å and this value coincide with three times to α-bcc lattice space (1.17 Å). The area which found double diffraction spots was judged metastable "zone" similar to the omega phase and induced embrittlement of SS410 material.

• KSTLE International Journal
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• 제2권2호
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• pp.133-137
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• 2001

This paper investigates the correlation between strip surface roughness and the surface of the work roll. As the actual temper mill(TM) is used, this data will be adopted to another actual temper mill for the application and operation of this experiment. Conclusions are as follows: Electro-discharge texturing(EDT) roll has homogeneous roughness distribution and shape, and also a sinuous peak surface and the life is 2 times longer than that of shot blast texturing(SBT) method. And the higher surface roughness of work roll, the more time is necessary at the EDT method. In the SBT method without the correlation of roughness, but impeller rotation speed with an uncontrollable peak count. The roughness of SBT roll is irregularity compared to that of EDT roll because the work roll roughness is transferred to the strip which was temper rolled, and produces a more desirable image and greater clarity to the color painted steel sheet.