• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.277-278
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• 2002

Magnetron and Ion beam sputtering were used to texture the air-bearing surface of magnetic recording sliders. Flying height measurements and Laser-Doppler interferometry were used to compare the 'flyability' of textured and untextured sliders. Lubricant redistribution on the disk surface caused by slider/disk interactions was investigated using scanning ellipsometry (Surface Reflectance Analyzer (SRA)). The results show that slider surface texture causes only small changes in the flying height of sliders but reduces slider in-plane and out-of-plane vibrations. Textured sliders were found to cause less lubricant depletion on the disk surface than untextured sliders.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1997년도 춘계학술대회논문집
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• pp.294-297
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• 1997

Two kinds of thermo-mechanical treatments(TMT) were applied to two AA3104 alloys. Tensile test, cupping and mesurement were conducted. Height and angular positions of earings in the drawn cups were explained by ODF on the contents of alloying elements. The tensile strengths measured in RD+45$^{\circ}$direction were generally lower than those measured in RD and TD directions. The textures of the experimental alloys were determined as shear texture {100}<011> and Cube texture {100}<001> by ODF's. Some optimum ratio of shear texture {100}<011> and Cube texture {100}<001> for reducing earings was found.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 춘계학술대회 논문집
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• pp.477-479
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• 2008

Drawability and other mechanical properties of sheet metals are strongly dependent on their crystallographic orientations. In this paper the formability of the AA 5052 Al alloy sheets was investigated after asymmetric rolling and subsequent heat treatment. In most cases, after asymmetric rolling specimens showed a fine grain size and subsequent heat treated specimens showed that the ND//<111> texture component were observed. The anisotropy of formability is often described by the plastic strain ratios (r-value) as a function of the angle to the rolling direction in sheet metal. For a good formability, a high r-value is required in sheet metals. In the asymmetry rolled and subsequent heat treated Al alloy sheet, the variation of the plastic strain ratios have been investigated in this study. The plastic strain ratios of the asymmetry rolled and subsequent heat treated AA 5052 Al alloy sheets were higher than those of the original Al sheets. These could be related to the formation of ND//<111> texture components through asymmetric rolling in Al sheet.

• 한국표면공학회지
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• 제32권3호
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• pp.317-330
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• 1999

The texture of electrodeposits changes from the orientation that places the lowest energy crystal facets parallel to the substrate under a condition of low ion concentration adjacent to the deposit, to the orientation that places the higher energy crystal facets parallel to the substrate as the ion concentration adjacent to the deposit increases. The electrodeposits have peculiar surface morphologies and microstructures depending on their textures, which in turn may affect their mechanical properties even when they are obtained in a similar electrolysis condition. The electrodeposits undergo recrystallization, when annealed. The recrystallization texture may be different from the deposition texture. These phenomena have been discussed.

• 산업식품공학
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• 제21권4호
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• pp.303-311
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• 2017

To automate cooking processes, quantitative descriptions are needed on how quality parameters, such as texture change during heating. Understanding mechanical property changes in foods during thermal treatment due to changes in chemical composition or physical structure is important in the context of engineering models and in precise control of quality in general. Texture degradation of food materials has been studied widely and softening kinetic parameters have been reported in many studies. For a better understanding of kinetic parameters, applied kinetic models were investigated, then rate constants at $100^{\circ}C$ and activation energy from previous kinetic studies were compared. The food materials are hardly classified into similar softening kinetics. The range of parameters is wide regardless of food types due to the complexity of food material, different testing methods, sample size, and geometry. Kinetic parameters are essential for optimal process design. For broad and reliable applications, kinetic parameters should be generated by a more consistent manner so that those of foods could be compared or grouped.

• 융복합기술연구소 논문집
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• 제12권1호
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• pp.1-5
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• 2022

This paper describes an algorithm for generating a terrain using a noise function and a height map as one of the procedural terrain generation methods. The polygon mesh data structure to represent the generated terrain concisely and render it is also described. The Perlin noise function is used as the noise technique for terrain mesh, and the height data of the terrain is generated by combining the four noise waves. In addition, the terrain height information can be also obtained from actual image data taken from the satellite. The algorithm presented in this paper generates the geometry part of the polygon topography from the height data obtained, and generated a material for texture mapping with two textures, that is, a diffuse texture and a normal texture. The validity of the terrain method proposed in this paper is verified through application examples, and its possibility can be confirmed through performance verification.

• Journal of Magnetics
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• 제16권3호
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• pp.220-224
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• 2011

Die-upset magnets from a mechanically-milled Pr(Co,In)$_5$-type alloy are known to have a peculiar texture; the easy magnetization axis (c-axis) is perpendicular to the pressing direction. This peculiar texture is thought to be linked closely to the anisotropic mechanical properties of Pr(Co,In)$_5$-type hexagonal compounds. The hardness of the Pr(Co,In)$_5$-type crystal was measured using selectively grown grains in an annealed $Pr_{17}Co_{82}In_1$ alloy button, and the crystallographic orientation was determined by observing the magnetic domain image. The hardness (549 VHN) on the plane with a 'cogwheel'-type domain image was significantly higher than that (510 VHN) on the plane with a 'cigar'-type domain image, indicating that the inter-layer bonding force between the (000l) basal planes is stronger than that between the (hki0) planes. This suggests that the most probable slip plane is the (hki0) plane parallel to the c-axis. During die-upsetting of the Pr(Co,In)$_5$-type alloys the deformation proceeds by (hki0) plane slip, and the c-axis rotates to ultimately become oriented perpendicular to the pressing direction. It is proposed that the peculiar texture in the die-upset Pr(Co,In)$_5$-type magnets is probably developed by slip deformation of the (hki0) plane of the Pr(Co,In)$_5$-type grains.

• KSTLE International Journal
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• 제1권1호
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• pp.12-20
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• 2000

Nano-wear and friction of carbon overcoated laser-textured and mechanically-textured computer hard disk were characterised after contact start/stop (CSS) wear test. Various analytical and mechanical testing techniques were employed to study the changes in topography, roughness, chemical elements, mechanical properties and friction characteristics of the coating arising from the contact start/stop wear test These techniques include: the atomic force microscopy (AFM), the continuous nano-indentation test, the nano-scratch test, the time-of-flight secondary ion mass spectroscopy (TOF-SIMS) and the auger electron spectroscopy (AES). It was shown that the surface roughness of the laser-textured (LT) bump and mechanically textured (MT) Bone was reduced approximately am and 7nm, respectively, after the CSS wear test. The elastic modulus and hardness values increased after the CSS test, indicating straining hardening of the top coating layer, A critical load was also identified fer adhesion failure between the magnetic layer and the Ni-P layer, The TOF-SIMS analysis also revealed some reduction in the intensity of C and $C_2$$F_59$, confirming the wear of lubricant elements on the coating surface.

• 한국식품과학회지
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• 제20권4호
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• pp.536-540
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• 1988

Blanching시간, chemical dipping, 냉동방법 및 저장기간이 냉동양송이의 texture, 색깔 및 수율에 미치는 영향을 연구한 결과는 다음과 같다. Whole mushroom의 경우 5분간 blanching한 것은 1-2분간 blanching한 것 보다 shear press값이 현저히 높았으며, 저장기간이 연장됨에 따라 shear press값이 매우 유의성 있게 증가했다. 그러나 냉동방법은 texture에 유의성 있는 영향을 주지 않았다. Sliced mushroom의 경우 blanching시간이 길어짐에 따라 shear press 값이 증가하기는 하나 유의성은 없었으며, 저장기간이 연장됨에 따라 texture가 현저히 tough 해짐을 알 수 있었다. 그리고 시료의 texture를 관능적으로 측정한 결과는 대체적으로 shear press 결과와 유사한 경향을 보였다. Chemical dipping 방법은 blanching 시간을 짧게하여 냉동양송이의 수율을 높히면서 저장중 색깔의 변화를 방지하는데 효과적이었으며, 특히 whole mushroom의 수율은 상당히 증진시킬 수 있었다. Sliced mushroom의 경우는 blanching time을 2분이하로 단축시키면 rotary slicer로 절단작업을 할 때 조직이 부스러져 생기는 중량손실이 증가하므로 2분 또는 그 이상의 blanching time이 필요했다.

• 한국재료학회지
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• 제33권11호
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• pp.439-446
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• 2023

Changes in the microstructure and mechanical properties of as-roll-bonded AA6061/AA5052/AA1050 three-layered sheet with increasing annealing temperature were investigated in detail. The commercial AA6061, AA5052 and AA1050 sheets with 2 mm thickness were roll-bonded by multi-pass rolling at ambient temperature. The roll-bonded Al sheets were then annealed for 1 h at various temperatures from 200 to 400 ℃. The specimens annealed up to 250 ℃ showed a typical deformation structure where the grains are elongated in the rolling direction in all regions. However, after annealing at 300 ℃, while AA6061 and AA1050 regions still retained the deformation structure, but AA5052 region changed into complete recrystallization. For all the annealed materials, the fraction of high angle grain boundaries was lower than that of low angle grain boundaries. In addition, while the rolling texture of the {110}<112> and {123}<634> components strongly developed in the AA6061 and AA1050 regions, in the AA5052 region the recrystallization texture of the {100}<001> component developed. After annealing at 350 ℃ the recrystallization texture developed in all regions. The as-rolled material exhibited a relatively high tensile strength of 282 MPa and elongation of 18 %. However, the tensile strength decreased and the elongation increased gradually with the increase in annealing temperature. The changes in mechanical properties with increasing annealing temperature were compared with those of other three-layered Al sheets fabricated in previous studies.