• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.910-913
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• 2003

In order to enhance performance, stability, and brightness of inorganic blue-light emitting EL device, barrier layer structure and pulsed laser annealing(PLA) treatment were introduced. The barrier layer structure was utilized for improving brightness of the device and instead of thermal annealing, pulsed laser annealing process was used. From this study, optimum barrier layer thickness and number of pulsed laser irradiation are established.

• Journal of Magnetics
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• 제3권1호
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• pp.15-20
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• 1998

A newly designed magnetic annealing apparatus was used for the treatment of Fe-3%Si steels. With the help of this device, the effect of magnetic annealing on magnetostriction was studied in a wide spectrum of external elastic stresses. It was shown that magnetostriction properties of Fe-Si steels were improved in the compressed state through magnetic annealing, while those in the unstressed state or under tensiion were found to be practically unchanged.

• 한국분말재료학회지
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• 제18권6호
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• pp.552-561
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• 2011

This study attempted to manufacture a Cu-15 at.%Ga coating layer via the cold spray process and investigated the effect of heat treatment environment on the properties of cold sprayed coating material. Three kinds of heat treatment environments, $5%H_2$+argon, pure argon, and vacuum were used in this study. Annealing treatments were conducted at $200{\sim}800^{\circ}C$/1 hr. With the cold sprayed coating layer, pure ${\alpha}$-Cu and small amounts of $Ga_2O_3$ were detected in the XRD, EDS, EPMA analyses. Porosity significantly decreased and hardness also decreased with increasing annealing temperature. The inhomogeneous dendritic microstructure of cold sprayed coating material changed to the homogeneous and dense one (microstructural evolution) with annealing heat treatment. Oxides near the interface of particles could be reduced by heat treatment especially in vacuum and argon environments. Vacuum environment during heat treatment was suggested to be most effective one to improve the densification and purification properties of cold sprayed Cu-15 at.%Ga coating material.

• Composites Research
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• 제22권2호
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• pp.1-6
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• 2009

감마선 조사된 초고분자량폴리에틸렌(UHMWPE)을 다양한 온도조건으로 열처리하여 기계적 물성변화를 구하였다. 열처리 조건은 어닐링(annealing)과 재용융(remelting) 온도범위를 선정하여 열처리하였다. $130^{\circ}C$ 이하의 어닐링 처리에 의해 강도와 파단시 연신율, 경도의 변화는 별로 없었지만, $140^{\circ}C$ 이상의 재용융처리에서는 기계적 물성의 급격한 저하가 발생하였다. FTIR해석 결과, 감마선 전처리에 따라 형성된 프리래디컬이 산화되었음을 알았다. 이와 같은 기계적 성질의 변화거동으로 나타나는 정량적인 데이터는 다양한 인공관절 부품의 설계와 해석에 필요한 기초적인 자료로 이용될 수 있다.

• 열처리공학회지
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• 제11권3호
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• pp.216-226
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• 1998

Heat treatment conditions and the formation of microstructures were studied for improving the transformation-induced plasticity(TRIP) effect of retained austenite and mechanical properties of Fe-0.2%C-1.5%Si-1.5%Mn sheet steel. An excellent combination of elongation about 30% and high strength over 760MPa was achieved by processing of intercritical annealing and isothermal holding Intercritical annealing the sheet steel produced fine particles($1{\sim}2{\mu}m$) of retained austenite which were stabilized due to C enrichment by subsequent holding in bainite transformation range. Heat treatment conditions were depended on the shape and distribution of second phases as well as the volume fraction and stability of retained austenrte. In this work, the heat treatment condition of optimal strength-elongation balance was obtained by holding the steel at $400^{\circ}C$ for 200sec, after intercritical annealing at $790^{\circ}C$ for 300sec.

• 한국재료학회지
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• 제33권11호
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• pp.482-490
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• 2023

The purpose of this study was to analyze microstructural changes and evaluate the mechanical properties of TWIP steel subjected to variations in heat treatment, in order to identify optimal process conditions for enhancing the performance of TWIP steel. For this purpose, a homogenization heat treatment was conducted at 1,200 ℃ for 2 h, followed by hot rolling at temperature exceeding 1,100 ℃ and cold rolling. Annealing heat treatment is achieved using a muffle furnace in the range of 600 ℃ to 1,000 ℃. The microstructure characterization was performed with an optical microscope and X-ray diffraction. Mechanical properties are evaluated using micro Vickers hardness, tensile test, and ECO index (UTS × Elongation). The specimens annealed at 900 ℃ and 1,000 ℃ experienced a significant decrease in hardness and strength due to decarburization. Consequently, the decarburization phenomenon is closely related to the heat treatment process and mechanical properties of TWIP steel, and the effect of the microstructure change during annealing heat treatment.

• 센서학회지
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• 제25권4호
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• pp.252-256
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• 2016

Epitaxially grown GaN layers have a high surface state density, which typically results in a surface leakage current and a photoresponse in undesirable wavelengths in GaN optoelectronic devices. Surface passivation is, therefore, an important process necessary to prevent performance degradation of GaN UV photodetectors. In this study, we propose oxygen-enhanced thermal treatment as a simple surface passivation process without capping layers. The GaN UV photodetector fabricated using a thermal annealing process exhibits improved electrical and photoresponsive characteristics such as a reduced dark current and an enhanced photoresponsive current and UV-to-visible rejection ratio. The results of this study show that the proposed surface passivation method would be useful to enhance the reliability of GaN-based optoelectronic devices.

• 열처리공학회지
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• 제21권1호
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• pp.26-32
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• 2008

Effects of annealing treatment on microstructure and mechanical property of co-sputtered TiNi thin films were studied. As-deposited films showed amorphous state. However, above annealing temperature of $500^{\circ}C$ martensite phase (B19'), precipitate phase ($Ti_2Ni$) and a small amount of parent phase ($B_2$) were present, and phase transformation behaviors were three multi-step phase transformations $B19^{\prime}{\rightarrow}B_2$ and $B_2{\rightarrow}R-phase$ and $R-phase{\rightarrow}B19^{\prime}$. Increase of martensite transformation temperature, increase of microhardness and Young's modulus of TiNi films annealed above $500^{\circ}C$ were discussed in terms of precipitate phase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2015년도 제46회 하계학술대회
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• pp.1151-1152
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• 2015

Silicon zinc oxide (SZO) thin films were deposited via co-sputtering. Two kinds of post-treatment, furnace annealing and hot pressing, were carried out on the deposited SZO films. The effects of the post-treatment on the chemical bond and surface roughness of the deposited SZO films were analyzed as functions of the post-treatment conditions that were used. It was observed from the X-ray photoelectron spectroscopy (XPS) results that the amount of Si-O bonds in the SZO film drastically increased after the low-temperature furnace annealing. The experiment results showed that the hot pressing method would be favorable as it could improve the electrical characteristics of the SZO-TFTs.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.1810-1815
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• 2003

Tube hydroforming provides a number of advantages over conventional stamping process, including fewer secondary operation, weight reduction, assembly simplification, adaptability to forming of complex structural components and improved structural strength and stiffness. In this study, the effect of the heat treatment on the hydro-formability has been investigated. By using the mild steel tube bulging test is performed at various heat treatment conditions to evaluate the hydro-formability.