• 한국재료학회지
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• 제19권12호
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• pp.674-679
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• 2009

Yttria stabilized zirconia single crystals show plastic deformation at high temperatures by activating dislocations. The plastic deformation is highly dependent on crystallographic orientation. When the samples were deformed at different orientations, stress-strain curves changed by operating different slip systems. The strength of samples was also highly dependent on crystallographic orientation, i.e., samples without yield drop showed higher strength than that of samples exhibiting yield drop. The slip systems in the sample deformed along <112>, <111> and <001> agreed with the theoretical values of the plastic deformation, following Schmid's Law. Dislocations play a major role in the plastic deformation of this crystal. At the early stages of plastic deformation, all samples exhibited dislocation dipoles and, in the later stages, dislocation interactions occurred by forming nodes, tangles and networks. In this study, three different orientations, [11-2], [111] and [001] were employed to explain the plastic deformation behavior. A microstructural analysis was performed to elucidate the mechanism of the plastic behavior of this crystal.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.185-188
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• 2000

Crystal orientation of Ni$_{18}$ $Fe_{19}$ thin films prepared by facing targets sputtering system was investigated. FTS system can deposit a high quality thin film and control deposition conditions in wide range. T he crystallographic characteristics of Ni$_{18}$ $Fe_{19}$ thin films on variation of thickness and substrate tempera ture was investigated by XRD and AFM. As a result, we obtained Ni$_{18}$ $Fe_{19}$ thin films prepared at subst rate temperature room temperature, thickness 160nm and over revealed good crystal orientation to [111] direction.irection.

• 한국진공학회지
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• 제4권S1호
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• pp.97-101
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• 1995

We report the results of a real-time synchrotron x-ray scattering study of the growth of TiN thin films on Si(001) substrates by RF sputtering. Our experiemnts show that the morphology of the TiN films strongly depends on growth conditions. After the nucleation and growth takes place with random crystallographic orientation at the very early stage, the films grow with a preferred orientation. Such preferred orientation was found to depend on both the sputtering power and the carrier gases used in the sputtering. Generally, the final morphology assumes either(111) or (002) crystallographic orientation. Using Ar sputtering, a cross-over effect from(002) to (111) was observed at intermediate time. The nature of the observed morphological changes is discussed.

• 한국재료학회지
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• 제14권2호
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• pp.121-125
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• 2004

Nickel oxide (NiO) thin films were deposited on Si(100) substrates at room temperature by RF magnetron sputtering from a NiO target. The effects of plasma gas and RF power on the crystallographic orientation and surface morphology of the NiO films were investigated. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM) and atomic force microscopy (AFM) were employed to characterize the deposited film. It was found that the type of plasma gases affected the crystallographic orientation, deposition rate, surface morphology, and crystallinity of NiO films. Highly crystalline NiO films with (100) orientation were obtained when it was deposited under Ar atmosphere. On the other hand, (l11)-oriented NiO films with poor crystallinity were deposited in $O_2$. Also, the increase in RF power resulted in not only higher deposition rate, larger grain size, and rougher surface but also higher crystallinity of NiO films.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 추계학술발표회
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• pp.30-30
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• 1997

• 한국초전도ㆍ저온공학회논문지
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• 제24권3호
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• pp.35-40
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• 2022

To fabricate large grain YBCO bulk superconductors by melt process, Sm123 single crystal with a high melting point are mostly used as seeds. However, it also uses Y123 film deposited on MgO single crystal substrate. This study investigated the growth behavior of the Y123 grain during a melt process when single grain YBCO bulk was used as a seed. Single grain Y123 bulk was grown when the seed size was small. When the seed size was relatively large, multiple grains were grown but the grains were still large. Y123 seed crystal was completely decomposed during high temperature anneal at 1040℃ and new Y123 crystals were nucleated during a slow cooling stage below a peritectic temperature. Thereafter, newly formed Y123 crystals from the seed area are thought to grow into the Y1.8 powder compact. The crystallographic orientations of newly nucleated Y123 grains are independent of the crystallographic orientation of Y123 seed. It is thought that the crystallographic orientation of newly nucleated Y123 crystal can be controlled by using Y211-free Y123 single crystal as a seed of homo-seeding melt growth.

• 대한전기학회논문지
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• 제43권6호
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• pp.965-970
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• 1994

ZnO transparent conducting oxide thin films have been prepared by Pyrosol deposition method and the effects of the different experimental variables on the electrical resistivity and optical transmittance of the prepared films have been investigated in details. The best film with a resistivity of about 8 X 10S0-2TΩcm and transmittance about 80% has been obtained at the substrate temperature of 4$25^{\circ}C$ by using HS12T+CHS13TOH(1:3) solvent and NS12T carrier gas after annealing at 20$0^{\circ}C$ for 40 minutes in vacuum. Furthermore, We have also found the effect of substrate temperature on crystallographic orientation and surface morphology. Annealing of the as-deposited film in vacuum leads to a substantial reduction in resistivity without affecting the optical transmittance and crystallographic orientation.

• 대한기계학회논문집A
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• 제28권5호
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• pp.547-553
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• 2004

A hemispherical asperity moving over a flat plane is simulated based on classical molecular dynamics. The asperity and the plane consist of silicon atoms whose interactions are governed by the Tersoff three-body potential. The gap between the asperity and the plane is maintained to produce attractive normal force in order to investigate the adhesive friction and wear. The simulation focuses on the influence of crystallographic orientation of the contacting surfaces and the moving direction. It is demonstrated that the adhesive friction and wear are lower when crystallographic orientations of the contacting surfaces are different, and also depend on the moving direction relative to the crystal1ographic orientation.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 1996년도 춘계연구발표회 논문개요집
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• pp.24-25
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• 1996

• 한국재료학회:학술대회논문집
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• 한국재료학회 1997년도 한국재료학회 추계학술발표회
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• pp.145-145
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• 1997