• Title/Summary/Keyword: Lattice preferred orientation

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Rock Deformation and Formation of LPO of Minerals in the Upper Mantle: Implications for Seismic Anisotropy (맨틀상부에서 암석의 변형 및 광물의 격자선호방향(LPO) 형성과 지진파 비등방성과의 연계성)

  • Jung, Hae-Meong
    • The Journal of the Petrological Society of Korea
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    • v.21 no.2
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    • pp.249-261
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    • 2012
  • Olivine is a dominant mineral in the upper mantle and is elastically very anisotropic. When olivine is deformed under stress at high pressure and high temperature, lattice preferred orientation (LPO) is formed. It is known that the LPO of olivine is affected by water, stress, and pressure. In this paper, I reviewed the papers dealing with the effects of water, stress, and pressure on the LPO of olivine, summarized the papers on the LPOs of olivine in natural mantle rocks, and discussed its implications for seismic anisotropy in the upper mantle. In addition, I also described four types of LPOs of orthopyroxene recently found in natural spinel lherzolite.

Preferred Orientation and Microstructure of Zinc Electrodeposit in acid Chloride Solution (우선배향과 두절경조직)

  • 예길촌;박계생;손경옥
    • Journal of the Korean institute of surface engineering
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    • v.16 no.4
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    • pp.173-187
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    • 1983
  • Zinc was electrodeposited at temperature from 20$^{\circ}C$ to 60$^{\circ}C$ over the ranges of the current density from 2 to 20 A/dm2 in acid chloride bath. The cathode overpotentials increased with increasing current density and decreasing tem-perature. The (10$.$3)-(10$.$2) preferred orientation developed at cathode overpotentials below about 450mV, the (10$.$3)(10$.$2)-(10$.$1) texture developed at overpotentials between 500mV and 950mV, and the (00$.$1) (10$.$3) texture developed at cathode overpotentials about 1000mV. The (00$.$1) (10$.$3) preferred orientation was also formed at the lower potentials between 400mV and 850mV at temperatures above 40$^{\circ}C$. The preferred orientations of the zinc deposits was discussed was discussed with both cathode overpo-tential and surface energy of deposit lattice planes. The pyramid type of structure with macrostep developed at low cathode overpotentials and the truncated pyramidal type developed at higher overpotenial.

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Crystallography Analysis of the β-Mg17Al12 Precipitates by the Secondary Constrained Coincident Site Lattice Model

  • Huang, Xuefei;Huang, Weigang
    • Applied Microscopy
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    • v.45 no.4
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    • pp.230-235
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    • 2015
  • Crystallographic models are effective tools to interpret, calculate and even to predict the preferred crystallographic morphologies of precipitates in various precipitation systems. The present study gives an introduction on the recently developed secondary constrained coincident site lattice (II-CCSL) model. Using the II-CCSL model, the interface matching condition of the ${\beta}-Mg_{17}Al_{12}$ precipitates with ${\alpha}-Mg$ matrix in an aged AZ91 alloy has been analyzed to rationalize the morphologies of the precipitates. The results show that the characteristic crystallographic features of the observed ${\beta}-Mg_{17}Al_{12}$ precipitates, i.e., the habit plane of the ${\beta}-Mg_{17}Al_{12}$ lath with a Burgers orientation relationship (OR) and the growth direction of the ${\beta}-Mg_{17}Al_{12}$ with a Crawley OR exhibit a better lattice matching degree than their vicinal orientations. Moreover, the Crawley OR is preferred to the Burgers OR due to a better lattice match.

Crystal Structure Refinement of $SnO_{2}$ Thin Film Using X-ray Scattering (X-선 산란을 이용한$SnO_{2}$ 박막의 결정구조 정밀화)

  • Kim, Yong-Il;Nam, Seung-Hoon;Park, Jong-Seo
    • Proceedings of the KSME Conference
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    • 2003.11a
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    • pp.1939-1943
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    • 2003
  • The precise structural analysis of $SnO_{2}$ thin film, which was prepared by PECVD and thickness 2400 ${\AA}$, was tried to do the structural refinement using X -ray diffraction data. The observed diffraction patterns of $SnO_{2}$ thin film had the strongly preferred orientation effect. WIMV method was used to correct the preferred orientation effect. The final weighted R-factor, $R_{WD}$ was 7.92 %. The lattice parameters, a = b == 4.7366(1) ${\AA}$ and c = 3.1937(1) ${\AA}$, were almost in accordance with ones of $SnO_{2}$ powder.

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An Investigation of Preferred Orientation and Microhardness of Nickel-Tin and Tin-Zinc Alloy Electrodeposits on Mild Steel (연강에서의 닉켈-주석과 주석-아연합금 전착층의 우성배향와 미소경도에 관한 연구)

  • Ahn, Deog-Su;Pyun, Su-Il
    • Journal of the Korean institute of surface engineering
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    • v.13 no.3
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    • pp.146-154
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    • 1980
  • The effects of various electrodeposition conditions (deposition temperature and cathode current density) on preferred orientation and microhardness of electrodeposited Ni-Sn and Sn-Zn alloys were studied. At deposition temperatures from 25$^{\circ}$ to 95$^{\circ}C$ and constant cathode current density of 270 and 530 A/$m^2$ Ni-Sn and Sn-Zn were codeposited in chloride-fluoride acid and stannate-cyanide alkaline electrolyte bath respectively. Ni-Sn alloy deposited at temperatures from 25$^{\circ}$ to 35$^{\circ}C$ was composed of single phase of $Ni_3Sn_4$ with 73 wt.% Sn and the one deposited at temperatures from 45$^{\circ}$ to 95$^{\circ}C$ was made of multiphase mixture of NiSn, $Ni_3Sn_2$ and $Ni_3Sn_4$ with nearly equiatomic composition (65.5 wt.% Sn). The random orientation of thermody-namically metastable NiSn phase (hexagonal structure) predominated at deposition temperature range 25$^{\circ}$-45$^{\circ}C$, and the strong (110) preferred orientation was found at 65$^{\circ}$-85$^{\circ}C$ and then disappeared again at 95$^{\circ}C$. The microhardness of Ni-Sn deposits increased with deposition temperature up to 85$^{\circ}C$, and then decreased at constant cathode current density. The preferred orientation and the maximum microhardness were discussed in terms of lattice contractile stress which result from desorption of hydrogen atom absorbed in deposit lattice. The Sn content of Sn-Zn alloy deposits increased with deposition temperature up to 75$^{\circ}C$, and then decreased at constant cathode current density of 530 A/$m^2$. It also decreased with cathode current density up to 530 A/$m^2$, and then increased at constant deposition temperature of 25$^{\circ}C$. Sn-Zn alloy deposits were composed of two-phase mixture of ${beta}$-Sn and Zn. The preferred orientations of ${beta}$-Sn (tetragonal structure) changed with deposition temperature. The microhardness of Sn-Zn deposits decreased with deposition temperature. It also increased with cathode density up to 530 A/$m^2$, and then decreased at constant deposition temperature of 25$^{\circ}C$. The microhardness of Sn-Zn deposits was observed to be determinded more by the Sn content than by the preferred orientation.

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Microstructure of brass electrodeposits in cyanide solution (시안화 황동도금욕을 사용한 黃銅電着層의 현미경조직)

  • Ye, Gil-Chon;Kim, Jong-Kwan
    • Journal of the Korean institute of surface engineering
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    • v.17 no.4
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    • pp.106-119
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    • 1984
  • Brass was electrodeposited over the range of the current densities from 2 to 8 A/$dm^2$ in cyanide bath at 20 and 40$^{\circ}C$. The cathode overpotential increased and the cathode efficiency was decreased respectively with decreasing temperature, increasing current density and addition of organic substance. The perferred orientation of the deposits were associated with the cathode overpotential and the nucleation energy of lattice planes. The (111) preferred orientation developed at the low current density and low cathode overpotential (440-520mV). On the other hand, the (111)+(100) preferred orientation developed at higher cathode overpotential (528-680mV). The (111)+(100) preferred orientation developed over the whole range of overpotential in the cyanide solution with organic additive. The copper content of deposit decreased with increasing current density and decreasing temperature. The morphology of the deposits with no additive was the polygonal body type of structure and the structure of the cross section was columnar structure. The morphology of the deposits with additive, on the other hand, was fine crystallite type of structure. And the structure of the cross section of them was the finer granular structure.

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Lattice Preferred Orientation of Amphibole in Amphibole-rich Rocks from Mt. Geumgye, Yugu, Gyeonggi Massif, South Korea (경기육괴 남서부 유구 지역 금계산에 분포하는 각섬암류 내 각섬석의 격자선호방향)

  • Kim, Junha;Jung, Haemyeong
    • Korean Journal of Mineralogy and Petrology
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    • v.35 no.3
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    • pp.259-271
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    • 2022
  • Lattice preferred orientation (LPO), which shows a specific lattice-orientation of minerals, is affected by the deformation conditions of minerals. Because of this reason, LPO is very useful to study the deformation conditions of the minerals and the rocks. In this study, we collected amphibole-rich rocks from the Geumgye Mountain, Chugye-ri, Yugu-eup, Chungcheongnamdo, located in the southwestern part of the Gyeonggi Massif, and analyzed the LPO of amphibole and plagioclase using electron backscattered diffraction. Two types of LPOs of amphibole, type I and type IV, were observed in Yugu amphibole-rich rocks. Our data suggest that the amphibole-rich rocks in Yugu were deformed by rigid body rotation regardless of the LPOs and grain size of amphibole, and the LPOs are considered to have been affected by the degree of deformation (i.e. strain). In the low strained amphibole-rich rock, a strong type I LPO and a large grain size of amphibole were observed. On the other hand, in the highly strained amphibole-rich rocks, a weak type IV LPO and a small grain size of amphibole were observed. The various degree of deformation observed in the Yugu amphibole-rich rocks were also observed in the adjacent peridotites, indicating that the rocks in Yugu experienced various levels of deformation.

Effects of Chemical Vapor Deposition Parameters on The Hardness and the Structural Characteristics of TiN Film (TiN피막의 경도 및 구조적 특성에 미치는 화학증착 조건의 영향)

  • Shin, Jong-Hoon;Lee, Seong-Rae;Baek, Young-Hyun
    • Journal of the Korean institute of surface engineering
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    • v.20 no.3
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    • pp.106-117
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    • 1987
  • The microhardness and the structural characteristics of the chemically vapor deposited TiN film on the 430 stainless steel substrate have been investigated with various deposition parameters such as the deposition time, the total flow rate, the flow rate ratio $(H_2/N_2)$, and the deposition temperature. The most important factor to affect the microhardness of the TiN film in this study was the denseness of the structure in connection with the degree of the lattice strain. The relationship between the lattice parameter changes and the grain size variation under all deposition conditions generally followed the grain boundary relaxation model. The (111) preferred orientation prevailed in the early stage of the deposition conditions, however, the (200) preferred orientation was developed in the later stage. The surface morphology at optimum conditions displayed a dense diamond shaped structure and the microhardness of the films was high (1700-2400Hv) regardless of the type of the substrates used.

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The Evolution of Preferred Orientation and Morphology of NiO Thin Films under Variation of Plasma Source and RF Power (Plasma source와 RF power에 따른 NiO박막의 우선배향성 및 표면형상)

  • Hyunwook Ryu;Park, Jinseong
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2003.11a
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    • pp.121-121
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    • 2003
  • NiO thin films are very attractive for use as an antiferromagnetic layer, p-type transparent conducting films, in electrochromic devices and functional sensor layer for chemical sensors, due to their excellent chemical stability, as well as optical, electrical and magnetic properties. In addition, (100)- and (111)-oriented NiO films can be used as buffer layers on which to deposit other oriented oxide films, such as c-axis-oriented perovskite-type ferromagnetic films and superconducting films, because of the similarity in symmetry of oxygen ion lattice and lattice constants between the NiO films and the oriented oxide films. Thus, controlling the crystallographic orientation and surface roughness of the NiO films for a buffer layer are very important.

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