• Corrosion Science and Technology
• /
• 제3권2호
• /
• pp.54-58
• /
• 2004

Effects of texture on the electrochemical behaviors of single grains in polycrystalline zinc were investigated using a capillary-based micro-droplet cell. Pontiodynamic sweeps and capacity measurements were carried out in pH 9 borate buffer solution. The cyclic voltammograms and the capacity measurements on single grains with different crystallographic orientations in polycrystalline Zn showed a strong dependence of oxide growth on crystallographic grain orientation. The total charge consumed for oxide formation and the inverse capacity increased with an increase of surface packing density of grain. suggesting the oxide formation was greater on grains with higher surface packing density.

• 분석과학
• /
• 제11권4호
• /
• pp.316-320
• /
• 1998

An image analysis was used for the interpretation of microstructures of ferrous metal artifacts. For the purposes, various microstructural features such as average grain size, phase area, shape factor, and composition of the inclusions, were parameterized for the information about manufacturing techniques such as casting, heating and tempering. The carbon content was determined through the evaluation of the amount of pearlite phase. As the amount of pearlite phase increased the shape factor also increased. Grain size was relatively smaller in trans-section than in cross-section. The manufacturing direction was trans-sectional because the orientation of inclusions was elongated lengthwise. All inclusions was of silicate groups and the manufacturing temperature was estimated up to $1450^{\circ}C$.

• 한국분말재료학회지
• /
• 제5권4호
• /
• pp.303-311
• /
• 1998

Hard materials such as hardmetal, coated hardmetal, cermet, ceramics and diamond or c-BN sintered compact are a kind of grain-dispersed alloy with high volume of hard particles. These are used for cutting tools, wear-resistant tools, rock bits, high pressure apparatus, etc. The annual production in Japan is about 1.7 billion dollars (200 billion yen). This is greatly owed to the development in science and technology which has been accomplished by applying new concepts such as fine or uniform grain microstructure, orientation of crystal grains, functionally graded material, artificial lattice and coherent bonding in recent years. In this review, the development in recent years in Japan is briefly summarized.

• Journal of information and communication convergence engineering
• /
• 제7권4호
• /
• pp.530-534
• /
• 2009

C-axis-oriented ZnO thin films were successfully deposited on p-Si (100) in an RF magnetron sputtering system. Deposition conditions such as deposition power, working pressure, and oxygen gas ratio $O_2/(O_2+Ar)$ were varied. Crystalline structures of the deposited ZnO films were investigated by a scanning electron microscope (SEM) technique. Results show that the deposition parameters can have a strong impact on the preferred orientations and grain sizes of the deposited ZnO films.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
• /
• pp.332-333
• /
• 2008

DC magnetron sputtering was used to deposit p-type polycrystalline silicon on n-type Si(100) wafer. The influence of film microstructure properties on deposition parameters (DC power, substrate temperature, pressure) was investigated. The substrate temperature and pressure have the important influence on depositing the poly-Si thin films. Smooth ploy-Si films were obtained in (331) orientation and the average grain sizes are ranged in 25-30nm. The grain sizes of films deposited at low pressure of 10mTorr are a little larger than those deposited at high pressure of 15mTorr.

• 대한기계학회논문집A
• /
• 제20권5호
• /
• pp.1516-1523
• /
• 1996

The present study is concerned with the development of anisotropy and deformation texture in polycrystals. The individual grain in an aggregate is assumed to experience the viscoplastic dedformation with crystallographic slip that unsure uniquenessof the active slip systems and shearing rate onthese systems. Two different methods for updating the grain orientation are examined. Texture development for some deformation modes such as plane strain compression, uniaxial tension and simple shear are found. Changes in anisotropic flow potential due to texture development during large deformation are also given. Anisotropic behavior of polycrystals with defferent textures are examined.

• 한국세라믹학회지
• /
• 제50권3호
• /
• pp.212-217
• /
• 2013

Ultra hard TiN coatings were fabricated by DC and ICP (inductively coupled plasma) magnetron sputtering techniques. The effects of ICP power, ranging from 0 to 300 W, on the coating microstructure, crystallographic, and mechanical properties were systematically investigated with FE-SEM, AFM, HR-XRD and nanoindentation. The results show that ICP power has a significant influence on the coating microstructure and mechanical properties of TiN coatings. With an increasing ICP power, the film microstructure evolves from an apparent columnar structure to a highly dense one. Grain sizes of TiN coatings decreased from 12.6 nm to 8.7 nm with an increase of the ICP power. A maximum nanohardness of 67.6 GPa was obtained for the coatings deposited at an ICP power of 300 W. The crystal structure and preferred orientation in the TiN coatings also varied with the ICP power, exerting an effective influence on film nanohardness.

• 한국표면공학회지
• /
• 제41권6호
• /
• pp.287-291
• /
• 2008

Reactively magnetron sputtered TiN films were deposited on Si wafers under varying bias voltage and characterized by X-ray diffraction, field-emission scanning electron microscopy and Nanoindentation. The films deposited under an Ar + $N_2$ atmosphere exhibited a mixed (200)-(111) orientation with a strong (200) texture, which subsequently changed to a strong (111) texture with increasing bias voltage. The changes in texture and grain size of the TiN thin films are due to one or a combination of factors such as strain energy, surface free energy, surface diffusivity and adatom mobility. The influence of each factor depends on the processing conditions. The average deposition rate and grain size were calculated from FE-SEM images of the films indicating that the deposition rate was lower at the films deposited under bias voltage.

• 한국전기전자재료학회논문지
• /
• 제33권6호
• /
• pp.450-453
• /
• 2020

In this study, ZnO:Ga thin films were fabricated on a glass substrate using various Ar flows by an RF magnetron sputter system at room temperature. The dependencies of Ar flow on different properties were investigated. An appropriate control over the Ar flow led to the formation of a high-quality thin film. The ZnO:Ga films were formed as a hexagonal wurtzite structure with high (002) preferential orientation. The films exhibited a typical columnar microstructure and a smooth top face. The average transmittance was 85~89% within the visible area. By decreasing the Ar flow, the sheet resistance was decreased due to an increase in the grain size and a decrease in the root mean square roughness. The lowest sheet resistance of 86 Ω/□ was obtained at room temperature for the 40 sccm Ar flow.

• Journal of Magnetics
• /
• 제5권4호
• /
• pp.143-146
• /
• 2000

In this study, the magnetic properties of CoCrPt films (far longditudinal recording) on a novel VMn underlayer were measured and compared with similar films on conventional Cr underlayers. It was found that the VMn film had (200) preferred orientation and the lattice constant was about 0.2967 nm, which is slightly larger than that of the Cr film, 0.2888 m. The grain size of the VMn film was 9.8 nm at 30 m thickness, about 39% smaller than that of a similarly deposited Cr. The CoCrPt/VMn films showed higher coercivity in comparison with the CoCrPt/Cr films. The coercivity increase is attributed to the increased Co (11.0) texture, improved lattice matching between Co (11.0) and VMn (200), and lower stacking fault density. V or Mn must have diffused into the CoCrPt magnetic layer uniformly rather than preferentially along grain boundaries. This reduced Ms at higher substrate temperature.