• Journal of Advanced Marine Engineering and Technology
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• v.18 no.1
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• pp.114-122
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• 1994

A cold temperature control system for the BAF(batch annealing furnace) has been established in order to reduce energy consumption to imrpove productivity and stabilize the properties of products. Therefore we confirmed a relation between annealing cycle time and atmospheric gas, changing annealing cycle time according to BAF temperature with time during heating and actual temperature measurements cold spot during soaking. The results of the temperature variation effect on the batch annealing are as follows. 1) Cooling rate is increasing gradually with increasing atmospheric gas flow, but heating rate is hardly increasing without atmospheric gas component. Heating time is reduced to one half with increasing atmospheric gas flow rate and changing of atmospheric gas component from HNx to Ax gas and annealing cycle time is reduce to 2.7 times. 2) With enlarging the difference between furnace temperature and soaking temperature at the HNx BAF, heating time becomes short, but cooling time is indifferent. 3) If temperature difference of 300.deg. C in the temperature change of cold spot according to the annealing cycle control temperature, Hi-CON/H2BAF is interchanging at each other at 26hours, but HNxBAF at 50 hours. 4) Soaking time at batch annealing cycle determination is made a decision by the input coil width, and soaking time for quality homogenization of 1219 mm width coil must be 2.5 hours longer then that of 914mm width coil for the same coil weight at Hi-CON/H2BAF. But, it is necessary to make 2 hours longer at HNxBAF.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.17 no.4
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• pp.130-136
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• 2018

In this paper, the effects of different 3D printing parameters including laminated angle and annealing temperature, were observed for their effects on tensile testing. In 3D printing, a filament is heated quickly, extruded, and then cooled rapidly. Because plastic is a poor heat conductor, it heats and cools unevenly causing the rapid heating and cooling to create internal stress within the printed part. Therefore, internal stress can be removed using annealing and to increase tensile strength and strain. During air cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 46% while the tensile stress tended to increase by 7.4%. During oven cooling at annealing temperature $140^{\circ}C$, the strain of laminated angle $45^{\circ}$ specimens tended to increase by 34% while the tensile stress tended to increase by 22.2%. In this study, we found "3D printing with annealing" eliminates internal stress and increases the strength and stiffness of a printed piece. On the microstructural level, annealing reforms the crystalline structures to even out the areas of high and low stress, which created fewer weak areas. These results are very useful for making 3D printed products with a mechanical strength that is suitable for applications.

• Journal of the Korean Society for Heat Treatment
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• v.21 no.6
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• pp.293-299
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• 2008

In order to provide with fundamental data of the wrought Mg alloy for press forging, the effect of annealing temperature on the microstructure, texture development and tensile properties is studied in a commercial AZ31B Mg alloy sheet. Basal texture i.e. $(0001){\pm}5^{\circ}$[21$\bar{3}$0] is developed in a commercial AZ31B Mg sheet, and the texture is not changed considerably by annealing over $400^{\circ}C{\times}30min$, while (10$\bar{3}$0) component with high intensity can be observed due to abnormal grain growth. When the sheet is tensile-deformed with RD, $45^{\circ}$ and TD directions at room temperature, fracture strains are given by 25.8, 21.4 and 11.9% in the order of RD, $45^{\circ}$ and TD directions, respectively. With increasing annealing temperature up to $450^{\circ}C{\times}30min$, little change in mean grain size can be revealed by annealing below $300^{\circ}C{\times}30min$ but an abnormal grain growth, where some grains become significantly coarser than the rest, occurs by annealing above $400^{\circ}C{\times}30min$. The maximum tensile strain of around 25% is obtained by annealing below $300^{\circ}C{\times}30min$, but it is abruptly decreased to 16% by annealing above $400^{\circ}C{\times}30min$ owing to intergranular fracture of abnormal grown grains.

• Journal of the Korean Magnetics Society
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• v.2 no.2
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• pp.91-98
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• 1992

In a $Co_{67}Fe_{4.5}Nb_{2}Si_{10}B_{15}$ amorphous alloy ribbon the effect to two-step annealing on the soft magnetic properties has been studied. By two-step annealing method which the second annealing at low temperature of $310^{\circ}C$ for 2 hours is undertaken after the primary annealing at high temperature above $480^{\circ}C$ for 20 minutes at the vacuum state, the coercive force and the squareness are not changed nearly but the initial permeability at d.c. and the effective permeability at a.c. are remark-ably increased compared with the one-step annealing. The maxima of the initial permeability and the effective permeability at 1 kHz after the two-step annealing are 290,000 and 41,000, respectively, which are 30% higher than those of the one-step annealing. The change of magnetic properties with annealing temperature is discussed in terms of the residual stress, the domain size, the cluster and the crystalline phase.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.233-233
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• 2010

CdS thin films were deposited on glass substrates by R.F. magnetron sputtering method and some of the samples were treated by rapid thermal annealing (RTA) process. Effects of thermal annealing on structural and optical properties were investigated at different temperatures ranging from 100 to $600^{\circ}C$. The crystallographic structure of the films and the size of the crystallites in the films were studied by X-ray diffraction. The crystallite sizes were found to increase, and the X-ray diffraction patterns were seen to sharpen by annealing. Optical properties of the films were calculated using the envelope method and the photoluminescence measurements. The optical properties of the films were seen to be dependent on the film thicknesses. The energy gap of the films was found to decrease by annealing. The band edge sharpness of the optical absorption was seen to oscillate by thermal annealing. Annealing over $400^{\circ}C$ was seen to degrade the optical properties of the film. The best annealing temperature for the films was found to be $400^{\circ}C$ from the optical properties. It is observed that the CdS film annealed at $400^{\circ}C$ reveals the strongest UV emission intensity and narrowest full width at half maximum among the temperature ranges studied. The enhanced UV emission from the film annealed at $400^{\circ}C$ is attributed to the improved crystalline quality of CdS thin film due to the effective relaxation of residual compressive stress and achieving maximum grain size. The results show that heat treatments under optimal annealing condition can provide significant improvements in the properties of CdS thin films.

• Journal of IKEEE
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• v.23 no.2
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• pp.704-709
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• 2019

In this paper, the electrical characteristics of tunneling field effect transistor(TFET) was studied for different annealing conditions. The TFET samples annealed using hydrogen forming gas(4 %) and Deuterium($D_2$) forming gas(4 %). All the measurements were conducted in noise shielded environment. The results show that subthreshold slope(SS) decreased by 33 mV/dec after annealing process compared to before annealing. Under various temperature range, the noise is improved by average of 31.2 % for 10 atm Deuterium gas at $V_G=3V$ condition. It is also noticed that, post metal annealing with $D_2$ gas reduces the noise by average of 30.7 % at $I_D=100nA$ condition.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1762-1764
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• 1999

We investigated the annealing effect on generating pretilt angle and aligning liquid crystal (LC) using the photo-depolymerization reaction in this study. In case of rubbing polyimide (PI) surface with the side chain, pretilt angle tends to increase with increasing the annealing time. It is considered because the steric interaction is increased by annealing which cause the side chain to come back to original position. For obliquely irradiating ultraviolet (UV) light on PI surface, pretilt angle shows to $0^{\circ}$ and is increased by annealing. The pretilt angle in rubbed PI surface is much higher than in photo-aligned PI surface. It is attributed to the steric interaction and the number of LC molecular arrangement on azimuthal direction. In addition. in case of obliquely irradiating UV light on PI surface. it showed LC alignment to increase by annealing. It can be regarded due to the fact that the re-alignment of LC molecule is improved to residual polymer direction by annealing.

• Journal of Korean Vacuum Science & Technology
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• v.6 no.2
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• pp.79-83
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• 2002

As Ag does not form my silicide on Si surfaces, Ag wire is a candidate for self-assembled nanowire on the reconstructed and single-domain Si(5 5 12)-2 $\times$ 1. In the present study, various Ag coverages and post-annealing temperatures had been tested to fabricate a Ag nanowire with high aspect ratio. When Ag coverage was less than 0.03 ML and the post-annealing temperature was 500(C, Ag atoms preferentially adsorbed on the tetramer sites resulting in Ag wires with an inter-row spacing of ~5 nm. However, its aspect ratio is relatively small and its height is also not even. On the other hand, the Ag-posited surface completely loses its reconstruction even with the same annealing at 500 $\^{C}$ if the initial coverage exceeds 0.05 ML. But the additional subsequent annealing at 700$\^{C}$ and slow-cooling process recovers the well-ordered Ag chain with relatively high aspect ratio on the same tetramer sites. It can be understood that, in the double step annealing process, the lower temperature annealing is required for cohesion of adsorbed Ag atoms and the higher temperature annealing is for providing Ag atoms to the tetramer sites.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.8 no.6
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• pp.105-110
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• 2008

We have investigated the high temperature rapid thermal annealing of GaN epilayers in nitrogen atmosphere. Annealing has been performed in a rapid thermal annealing furnace at $950^{\circ}C$. The effect of rapid thermal annealing of GaN was studied by x-ray diffraction. The Bragg peak shifts toward larger angle as the annealing time increases. The full width at half maximum (FWHM) of the peak slightly increase, followed by decreases, and increases again as the thermal treatment time increases. The improvement of structural properties of the samples was observed after rapid thermal annealing under optimum conditions. This improvement in crystal quality is due to a reduction of the spread in the lattice parameter in epilayers.

• Journal of the Korean Ceramic Society
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• v.53 no.4
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• pp.450-455
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• 2016

Color change in single-crystal, yellow, red, purple, and colorless cubic zirconias (CZs) was investigated as a function of annealing in vacuum and air atmosphere at $800-1400^{\circ}C$ for 30 min, for development of a damascene process of plugging a precious metal paste at the elevated temperature. Coloring-element contents of the CZs were evaluated using WD-XRF, and the color change determined visually by naked eye, and using a digital camera and UV-Vis-NIR color analyzer. WD-XRF showed that all of the CZs had cubic-phase stabilizer elements and coloring elements. All CZs that underwent vacuum annealing exhibited a slight color change at $<900^{\circ}C$, while their colors began to change to black at $1100^{\circ}C$, and became opaque black at $1400^{\circ}C$. After air annealing, there was almost no color change up to $1400^{\circ}C$. Since red and purple CZs showed greater color difference (CD) values than the others, the degree of CD is likely to depend on the original color of the CZ due to the different stabilities of their coloring elements during annealing. Based on our results, it is suggested that annealing in air at $<900^{\circ}C$ is advantageous, and assorted colored CZs can be used for precious metal damascene.