• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03b
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• pp.112-115
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• 1999

The effect of intermediate annealing on the texture evolution in I.f steel was investigated by using X-ray texture measurement. After The sample was cold rolled to 80% reduction intermediate annealing was introduced to preform ${\gamma}$-fiber orientation grains in deformed matrix. The annealing time was varied between 30 and 3600 sec, These samples were cold rolled to 90% reduction and full annealed. By intermediate annealing final full annealed samples had very homogeneous ${\gamma}$-fiber orientation resulting in good deep drawability.

• Tribology and Lubricants
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• v.37 no.2
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• pp.62-70
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• 2021

The problem with intermetallics coating using the heat of molten casting is that the heat generated during combustion synthesis dissolves the coating and the substrate metal. This study investigates whether pre-annealing before synthesis can control the reaction heat, with the aim of Ni₃Al coating on the casting surface. Therefore, the effects of the annealing temperature and time on the combustion synthesis behavior of the powder compact of Ni-25at%Al after annealing were investigated. As results, the reaction heat when synthesized decreased as the annealing temperature was high and the annealing time was longer. This was attributed to the fact that Al was diffused to Ni particles during low temperature annealing and intermediate Ni-Al compounds were formed during high temperature annealing. After combustion synthesis, however, it was found that their microstructures were almost identical except for the amount of intermediate intermetallics. Furthermore, an annealing temperature above 450℃, at which intermediate compounds begin to form, is needed to prevent the dissolving problem during synthesizing. The intermetallics synthesized after annealing at higher temperature and prolonger annealing time showed a good wear resistance. This might be because much intermediate intermetallics of high hardness were remained in the microstructure.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.10a
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• pp.17-20
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• 2000

In order to improve the sheet formability of the ferritic stainless steel, the through-thickness textures of the recrystallized sample was modified by means of a thermomechanical treatment. An annealing process between the cold rolling reductions modified the preferred orientations throughout the thickness, which resulted in the modification of the final cold rolling texture as well as the final recrystallization texture. With the help of the modification of the recrystallization texture by the intermediate annealing, improvement of the sheet formability, i.e. an increase of the Lankford value.

• 제어로봇시스템학회:학술대회논문집
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• 1995.10a
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• pp.319-322
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• 1995

As a trend toward multi-product batch processes is increasing in Chemical Process Industry (CPI), multi-product batch scheduling has been actively studied. But the optimal production scheduling problems for multi-product batch processes are known as NP-complete. Recently Ku and Karimi [5] have studied Simulated Annealing(SA) and Jung et al.[6] have developed Modified Simulated Annealing (MSA) method which was composed of two stage search algorithms for scheduling of batch processes with UIS and NIS. Jung et al.[9] also have studied the Common Intermediate Storage(CIS) policy which have accepted as a high efficient intermediate storage policy. It can be also applied to pipeless mobile intermediate storage pacilities. In spite of these above researches, there have been no contribution of scheduling of CIS policy for chemical batch processes. In this paper, we have developed another MSA for scheduling chemical batch processes with searching the suitable control parameters for CIS policy and have tested the this algorithm with randomly generated various scheduling problems. From these tests, MSA is outperformed to general SA for CIS batch process system.

• Journal of the Korean Ceramic Society
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• v.32 no.8
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• pp.881-892
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• 1995

Sol-Gel derived ferroelectric PZT thin films were fabricated on ITO/Glass substrate. Two kinds of rapid thermal annealing methods, R-I (six times of intermediate and final annealing) and R-II (one final annealing after six times of intermediate annealing) were used for preparation of multi-coated PZT thin films. 2500$\AA$-thick PZT thin films were obtained by the R-I and R-II methods and characterized by microstructure and dielectric properties. In case of using R-II, the microstructure was finer than that of R-I and there was no distinguishable difference in dielectric properties of PZT thin films between the R-I and R-II methods. But dielectric properties were enhanced by increasing perovskite phase fraction with increasing annealing temperature. Measured dielectric constant of PZT thin film annealed at 62$0^{\circ}C$ using the R-I method was 256 at 1kHz. Its remanant polarization (Pr) and coercive field (Ec) were 14.4$\mu$C/$\textrm{cm}^2$ and 64kV/cm, respectively.

• Proceedings of the Korean Nuclear Society Conference
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• 2002.10a
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• pp.262.1-262
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• 2002

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.574-577
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• 2001

GaN thin films on sapphire were grown by rf magnetron sputtering with ZnO buffer layer. The dependence of GaN film quality on ZnO buffer layer was investigated by X-ray diffraction(XRD). The improved film quality has been obtained by using thin ZnO buffer layer. Using Auger electron spectroscopy(AES), it was observed that the annealing process improved the GaN film quality. The surface roughness according to the annealing temperatures(700, 900, 1100$^{\circ}C$) were investigated by AFM(atomic force microscopy) and it was confirmed that the crystallization was improved by increasing the annealing temperature. Photoluminescence at 8K shows a near-band-edge peak at 3.2eV with no deep level emission.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2000.04a
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• pp.202-205
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• 2000

The effect of two step cold rolling and intermediate annealing conditions on the microstructure and texture evolution in type 430 stainless steel has been investigated tin order to improve ridging characteristic and deep drawability. The rolling and recrystallization textures were examined by orientation distributionfunction(ODF) and electron backscattered diffraction(EBSD). The observation showed that the intensity of ${\gamma}$-fiber was increased with two-step cold rolling process and so ridging characteristic and deep drawability were considerably improved. The relation between these properties an texture evolution has been discussed.

• Journal of the Korean institute of surface engineering
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• v.27 no.4
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• pp.234-240
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• 1994

A large area impurity doping method for poly-Si TFT LCD has been developed. The advantage of this method is the doping of impurities into Si over a large area without mass separation and beam scanning. Phosphorus diluted in hydrogen was discharged by RF(13.56MHz) power and ions from discharged gas were accelerated by DC acceleration voltage and were implanted into deposited Si films. The annealing characteristic of this method was similar to that of the ion implantation method in the low doping concentration. Three mechanisms were evolved in the annealing characteristics of phosphorus doped Si films. Point defects annihilation and the retrogradation of dopant atoms at grain boundaries as a result of grain growth played a major role at low and high annealing temperature, respectively. However, due to the dopant segregation, the reverse annealing range existed at intermediate annealing temperature.

• Electrical & Electronic Materials
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• v.9 no.3
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• pp.251-258
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• 1996

Sol-Gel derived ferroelectric Pb(Z $r_{0.52}$ $Ti_{0.48}$) $O_{3}$ thin films have been fabricated on Pt/Ti/ $SiO_{2}$/Si substrate. Two kinds of fast annealing methods, F-I (six times of intermediate and final annealing) and F-II(one final annealing after six times of intermediate annealing) were used for preparation of multi-coated PZT thin films. As the annealing temperature was increased, high capacitance could be obtained, for instance, 2700.angs.-thick PZT thin film annealed at 680.deg. C had a capacitance value of approximately 20nF at 1kHz. In addition, it is found that the dielectric constant is a function of the perovskite phase fraction. In case of F-I method, PZT thin film had a remanent polarization(Pr) of 8-15.mu.C/c $m^{2}$ and a coercive field( $E_{c}$) of 35-44kV/cm according to annealing temperature, whereas PZT film fabricated by F-II method had as high as 24-25.mu.C/c $m^{2}$ and 48-59kV/cm, respectively. As a result of measuring Curie temperature, PZT thin film had a range of 460-480.deg. C by F-I method and more or less higher range of 525-530.deg. C by F-II method, which implied that different microstructures could cause the different Curie temperature. Through I-V measurement, leakage current of PZT thin film fabricated by F-I and F-II methods was 64nA/c $m^{2}$ and 2.2.mu.A/c $m^{2}$ in the electric field of 100kV/cm, respectively.y.y.y.