• Transactions of Materials Processing
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• v.21 no.4
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• pp.252-257
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• 2012

Crystallographic texture evolution during forming processes has a significant effect on the anisotropic flow behavior of crystalline material. In this study, a crystal plasticity finite element method (CPFEM), which incorporates the crystal plasticity constitutive law into a three-dimensional finite element method, was used to investigate texture evolution of a face-centered-cubic material - an aluminum alloy. A rate-dependent polycrystalline theory was fully implemented within an in-house program, CAMPform3D. Each integration point in the element was considered to be a polycrystalline aggregate consisting of a large number of grains, and the deformation of each grain in the aggregate was assumed to be the same as the macroscopic deformation of the aggregate. The texture evolution during three different deformation modes - uniaxial tension, uniaxial compression, and plane strain compression - was investigated in terms of pole figures and compared to experimental data available in the literature.

• Journal of Korea Game Society
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• v.17 no.6
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• pp.153-164
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• 2017

In spherical panoramic images, SURF, a feature description method for planar patterns, does not work correctly due to heavy spherical distortion. Since a plane pattern is distorted in a spherical image, the pattern search and replacement in a spherical panoramic image should be treated differently from the case of the planar image. This paper proposes a planar texture replacement method, which transforms a spherical panoramic image into a cubemap panoramic image, searches a pattern using SURF, replaces a plane pattern, and then converts it into a spherical panoramic image.

• Transactions of Materials Processing
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• v.33 no.5
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• pp.363-370
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• 2024

This study investigated the evolution behavior of microtexture developed in Ta-10W alloy during cold rolling. The changes in microtexture during the cold rolling process were experimentally analyzed using EBSD techniques. At relatively low rolling reductions (20%, 40%), θ-fiber and α-fiber textures were developed. However, as the reduction increased to 60% and 80%, strong α-fiber and γ-fiber textures were observed. The microtexture behavior was theoretically predicted using the VPSC polycrystal model under plane strain compression(PSC) and conditions considering deformation in the transverse direction. The VPSC model results under PSC predicted the strong development of θ-fiber texture at low reductions (20%, 40%) and the development of α-fiber and γ-fiber textures as the reduction increased to 60% and 80%. The VPSC model considering transverse deformation predicted results similar to the plane strain PSC at low reductions (20%, 40%), but as the reduction increased to 60% and 80%, it predicted that the development of α-fiber texture would be relatively weak, and the θ-fiber texture would still remain even at an 80% reduction. It was confirmed that the VPSC model considering transverse deformation more accurately predicts the evolution behavior of microtexture observed experimentally.

• Progress in Superconductivity
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• v.6 no.2
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• pp.133-137
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• 2005

We fabricated the Au/Ni template for YBCO coated conductors and evaluated texture formation and the microstructural evolution. The cube textured Ni substrate was fabricated by rolling and recrystallization annealing, and subsequently Au layer formed on the substrate by electroless-plating method. The texture was evaluated by pole-figure with x-ray goniometer with orientation distribution function (ODF) analysis. The surface roughness and grain boundary morphology of template were characterized by atomic force microscopy (AFM) We observed that Au layer deposited epitaxially on Ni substrate and formed a strong cube texture when plating time was optimized. The full-width at half-maximum (FWHM) was $8.4^{\circ}$ for out-of-plane and $9.98^{\circ}$ for in-plane texture for plating time of 30 min. Microstructural observation showed that the Au layer was homogeneous and dense without formation of crack/microcrack. In addition, we observed that root-mean-square (RMS) and depth of grain boundary were 14.6 nm and 160 $\AA$ for the Au layer, respectively, while those were 27.0 nm and 800 $\AA$ for the Ni substrate, indicating that the electoless-plated Au layer had relatively smooth surface and effectively mollified grain groove.

• Progress in Superconductivity and Cryogenics
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• v.4 no.2
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• pp.16-20
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• 2002

Bi-axially textured Ni tapes for YBCO coated conductors were Prepared by cold rolling and heat treatment of Ni Powder compacts. The Ni powder used in this study was 5 urn in particle size and 99.99 % in purity. The process of this study consists of filling of hi powder into a rubber mold, cold-isostatically Pressing and sintering of the powder compacts at 110$0^{\circ}C$ for 6h in 96 % Ar - 4 % H$_2$ atmosphere. The sintered compacts were cold rolled with a 5 % step reduction ratio into a 100 micron-thick tapes and then heat-treated at 100$0^{\circ}C$ for various time periods. The (200) texture of Ni tape was successfully developed through the recrystallization heat treatment of the cold rolled Ni tapes. At 100$0^{\circ}C$, the degree of texture of the heat-treated Ni tapes seems not to be significantly affected by the heat-treatment time. The short heat treatment of S min was sufficient to develop the complete (200) cube texture. The degree of in-Plane and out-of-plane texture of the prepared Ni tapes was 8-10$^{\circ}$. The heat treated Ni tapes consisted of equiaxed grains with a size 50-70 microns. and the AFM sol-face roughness was as smooth as 3 nm.

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2002.02a
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• pp.119-122
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• 2002

The NiO buffer layers for YBCO coated conductor were prepared on textured Ni substrates by MOCVD method and the degree of texturizing and the surface roughness were analyzed X-ray pole figure and AFM and SEM. Processing variables were oxygen partial pressure and substrate temperature. (200) textured NiO layer was formed at 450~$470^{\circ}C$ and oxygen partial pressure of 1.67 Torr. Out-of-plane($\omega$-scan) and in-plane($\Phi$-scan) texture were $10.34^{\circ}$ and $10.00^{\circ}$ respectively. The surface roughness estimated by atomic force microscopy was in the range of 3.1~4.6 nm.

• 한국초전도학회:학술대회논문집
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• v.10
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• pp.289-292
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• 2000

In order to evade the patent of Oak Ridge National Laboratory (RABiTS process) and search for more economical process, a new process for producing the biaxially textured Ni tape by electrodeposition has been investigated. Electrodeposition was performed in the modified Watts bath. The crystal orientations of electrodeposited Ni were analysed by X-ray pole figure, ${\phi}$-scan and ${\omega}$-scan. The electrodeposited Ni tape showed cube texture with good out-of plane(< 8${\circ}$) and in-plane alignment(< 20${\circ}$).

• Proceedings of the Korea Institute of Applied Superconductivity and Cryogenics Conference
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• 2003.10a
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• pp.24-26
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• 2003

We fabricated Ni and Ni alloy substrates for YBCO coated conductors. The Ni and Ni alloy substrate was fabricated by powder metallurgy technique and cold rolling. The texture of substrates had a strong 4-fold symmetry and ［111］∥ND texture after annealing temperature of 100$0^{\circ}C$. The measured full-width half-maximum (FWHM) of in-plane and out-of-plane was in the range of 6$^{\circ}$-10$^{\circ}$. The powder metallurgy technique is fabrication of the substrates for considered to be suitable for the application of YBCO coated conductors.

• Journal of Korea Multimedia Society
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• v.5 no.1
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• pp.94-104
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• 2002

This paper presents a new way of texture mapping on the Genus N object constructed over a single domain. The problem of 2D texture mapping is the discontinuity of texture domain at the virtual boundary on the object. Such phenomenon decreases smoothness of the object as well as looks unnatural. Especially it is necessary for the Genus N object of infinite coninuity to apply the seamless texture mapping. For seamless texture mapping, a multiperiodic function, which transforms a discontinuous function into a continuous function, is suggested. In some applications, however, the visual seams on the textured object provide more realistic appearance. Therefore, this research supports the interactive control from the discontinuity and the continuity across the boundary using the coefficient of the weight function.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.7
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• pp.680-686
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• 2006

Tin oxide$(SnO_2)$ thin films were prepared on glass substrate by Plasma Enhanced Chemical Vapor Deposition (PECVD) method. $SnO_2$ thin films were prepared using gas mixture of dibutyltin diacetate as a precursor and oxygen as an oxidant at 275, 325, 375, $425^{\circ}C$, respectively as a function of deposition temperature. The XRD peaks corresponded to those of polycrystalline $SnO_2$, which is in the tetragonal system with a rutil-type structure. As the deposition temperature increased, the texture plane of $SnO_2$ changed from (200) plane to denser (211) and (110) planes. Lower deposition temperature and shorter deposition time led to decreasing surface roughness and electrical resistivity of the formed thin films at $325\sim425^{\circ}C$. The properties of $SnO_2$ films were critically affected by deposition temperature and time.