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Journal of Central South University 2008年第S1期15卷 550-554页

作者：刘又文谢超方棋洪 College of Mechanics and Aerospace Hunan University

A theoretical model was suggested which describes the generation of the misfit dislocation dipole in the system of the viscoelastic matrix containing a circular stiff nanoscale *** critical condition of misfit dislocation dipole and the solution of equilibrium position were *** influence of the ratio of shear modulus,the misfit strain and viscosity on the equilibrium of the dislocation and critical parameter of inhomogeneity was *** result shows that the equilibrium position de increases with the increase of the ratio of original shear modulus and the effect decreases with the increase of viscosity of *** with the increase of viscosity of matrix,de first increases and then decreases and possesses maximum value when t=0.3τ and tends to a stable value when t≥1.0τ.Along with the increase of viscosity of matrix,Rc first decreases and then increases and possesses minimum value when t=0.3τ and tends to a stable value when t≥1.0τ.

关键词： nanoscale inhomogeneity viscoelastic misfit strain misfit dislocation dipole critical condition

misfit Dislocations in Strained-layer Semiconductor Heterostructures

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电子显微学报 1997年第4期 15-18页

ＭｉｓｆｉｔＤｉｓｌｏｃａｔｉｏｎｓｉｎＳｔｒａｉｎｅｄｌａｙｅｒＳｅｍｉｃｏｎｄｕｃｔｏｒＨｅｔｅｒｏｓｔｒｕｃｔｕｒｅｓＪ．Ｚｏｕ（ＥｌｅｃｔｒｏｎＭｉｃｒｏｓｃｏｐｅＵｎｉｔ＆ＡｕｓｔｒａｌｉａｎＫｅｙＣｅｎ... 详细信息

ＭｉｓｆｉｔＤｉｓｌｏｃａｔｉｏｎｓｉｎＳｔｒａｉｎｅｄｌａｙｅｒＳｅｍｉｃｏｎｄｕｃｔｏｒＨｅｔｅｒｏｓｔｒｕｃｔｕｒｅｓＪ．Ｚｏｕ（ＥｌｅｃｔｒｏｎＭｉｃｒｏｓｃｏｐｅＵｎｉｔ＆ＡｕｓｔｒａｌｉａｎＫｅｙＣｅｎｔｒｅｆｏｒＭｉｃｒｏｓｃｏｐｙａ...

关键词： Semiconductor Heterostructures misfit Dislocations

Thermoelectric Properties of misfit Layered Bismuth-Based Rhodium Oxides, (Bi,Pb)2Sr2Rh2Oy

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Journal of Materials Science and Chemical Engineering 2018年第7期6卷 97-103页

作者： Takuya Watanabe Hiroshi Irie Special Doctoral Program for Green Energy Conversion Science and Technology Interdisciplinary Graduate School of Medicine and Engineering University of Yamanashi Yamanashi Japan Clean Energy Research Center University of Yamanashi Yamanashi Japan

Rhodium oxides, including a misfitlayered structure with alternate stacking of a rock salttype layer and a hexagonal RhO2 layer, are expected to have good thermoelectric properties. Among them, the thermoelectric properties (electrical conductivity (σ), Seebeck coefficient (S), Figure of merit (ZT) and calculated thermal conductivity (κ) by S, σ, ZT, and absolute temperature (T)) of bismuth-based rhodium oxides ((Bi1-x,Pbx) 2Sr2Rh2Oy, x = 0 and 0.02, hereafter BSR and BPSR, respectively) were investigated. In comparison with Bi2Sr2Co2Oy (BSC) at 700°C, S and κ enhanced (increased S, 110 (BSR) and 105 μV K-1 (BPSR) from 85 μV K-1 (BSC) and decreased κ, 0.32 (BSR) and 0.50 W m-1 K-1 (BPSR) from 1.75 W m-1 K-1 (BSC)), whereas σ decreased (15 (BSR) and 31 S cm-1 (BPSR) from 70 S cm-1 (BSC)). BPSR reached the highest ZT value of 0.067 at 700°C, compared to those of 0.056 (BSR) and 0.027 (BSC).

关键词： Electroceramics Layered Rhodium Oxide misfit Layer Structure Thermoe-lectric Material Harman Method

misfit及misfit-GOODNESS在同址记录一致性中的应用研究

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四川地震 2021年第1期 33-38页

作者：李冬圣李小军贾炯蔡玲玲河北省地震局河北石家庄050021

对同址观测的地震计所记录的安静时段背景噪声、天然地方震、远震事件分别进行misfit分析,并参考misfit-GOODNESS的结果,给出两台地震计记录一致性的评价,对基于不同目的波形分析给出使用记录波形的合理频段范围,提高数据应用的可靠性。

关键词：同址 misfit misfit-GOODNESS 频段可靠性

Effect of applied stress on r'-rafting behavior in a Ni-based singlecrystal superalloy:experiments and finite element analysis

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Journal of Iron and Steel Research International 2019年第3期26卷 259-267页

作者： Yuan-chao Yu Yi Ru Yong Shang Yan-ling Pei Shu-suo Li Sheng-kai Gong School of Materials Science and Engineering Beihang University Beijing 100191 China

The effect of applied tensile stress on the r'-rafting behavior for a Ni-based single-crystal superalloy with more negative misfit was *** conducting interrupted creep tests at high temperature,it indicated that the increase in the applied stress accelerates the r'-rafting(directional coarsening of yr phase).In the early stage of rafting,the r'-cubes start interconnecting at the ends of the parallel-to-applied-stress r'-*** distributions of misfit stress,coherent strain and strain energy density of the r/r'phases are then calculated by finite element *** calculation results show that the rafting acceleration is mainly ascribed to the reduced strain energy density in the parallel-to-applied-stress r'-channel that is driven from the couple interaction of external load and misfit *** dislocation network formation,resulting from the misfit-induced increase in resolved shear stress,also contributes to the r'-rafting.

关键词： Ni-based superalloy High lattice misfit Rafting Finite element analysis misfit stress Strain energy density

Microstructure and phase composition of hypoeutectic Te–Bi alloy as evaporation source for photoelectric cathode

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 584-590页

作者： Bao-guang Wang Wen-hui Yang Hong-ye Gao Wen-huai Tian School of Materials Science and Engineering University of Science and Technology Beijing Faculty of Engineering Sciences Kyushu University

A hypoeutectic 60Te–40Bi alloy in mass percent was designed as a tellurium atom evaporation source instead of pure tellurium for an ultraviolet detection *** alloy was prepared by slow solidification at about 10^(-2) K·s^(-1).The microstructure,crystal structure,chemical composition,and crystallographic orientation of each phase in the as-prepared alloy were investigated by optical microscopy,scanning electron microscopy,X-ray diffraction,electron backscatter diffraction,and transmission electron *** experimental results suggest that the as-prepared 60Te–40Bi alloy consists of primary Bi_2Te_3 and eutectic Bi_2Te_3/Te *** primary Bi_2Te_3 phase has the characteristics of faceted *** eutectic Bi_2Te_3 phase is encased by the eutectic Te phase in the eutectic *** purity of the eutectic Te phase reaches 100wt%owing to the slow *** the eutectic phases,the crystallographic orientation relationship between Bi_2Te_3 and Te is confirmed as[0001]_(Bi2 Te3)//[1213]_Te and the direction of Te phase parallel to[1120]_(Bi2 Te3)is deviated by 18°from N(2111)_Te.

关键词： Te–Bi alloy microstructure orientation misfit

Distribution of Ge Self-Assembled Quantum Dots on Six Ge1 - x Buffer Layers

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Journal of Rare Earths 2004年第Z2期22卷 133-135页

作者： Joonyeon Chang Hyungjun Kim Nano Device Research Center Korea Institute of Science and TechnologySeoul 136-791Korea Department of Electrical EngireeringUniversity of California LosAngelesCA 90095-1595USA

The effect of buried misfit dislocation on the distribution of Ge self-assembled quantum dots (SAQDs) grown on a relaxed SiGe buffer layer was investigated. The strain field of arrays of buried dislocations in a relaxed SiGe buffer layer provided preferential nucleation sites for quantum dots. Burgers vector analysis using plan-view transmission electron microscopy (TEM) verified that the preferential nucleation sites of Ge SAQDs depended on the Burgers vector direction of corresponding dislocations. The measurement of the lateral distance between SAQDs and dislocations together with crosssection TEM observation clarified that the location of SAQDs was at the intersection of the dislocation slip plane and the top surface. The misfit strain should be an additional factor governing the uniformity in size, shape and distribution of Ge SAQDs.

关键词： misfit dislocation Ge self assembled quantum dots molecular beam epitaxy transmission electron microscopy

Laser molecular-beam epitaxy and second-order optical nonlinearity of BaTiO_3/SrTiO_3 superlattices

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Science China Mathematics 2000年第7期43卷 760-766页

作者：赵彤陈凡吕惠宾杨国桢陈正豪 Laboratory of Optical Physics Institute of Physics & Center for Condensed Matter Physics Chinese Academy of Sciences Beijing 100080 China

A series of c-axis oriented BaTiO3/SrTiO3 superlattices with the atomic-scale precision were epitaxially grown on single-crystal SrTiO3(100) substrates using laser molecular-beam epitaxy (LMBE). A periodic modulation of the intensity of reflection high-energy electron diffraction (RHEED) in BaTiO3 and SrTiO3 layers was observed and attributed to the lattice-misfit-induced periodic variation of the terrace density in film surface. The relationship between the second-order nonlinear optical sus-ceptibilities and the superlattice structure was systematically studied. The experimental and theoretical fitting results indicate that the second-order nonlinear optical susceptibilities of BaTiO3/SrTiO3 superlattices were greatly enhanced with the maximum value being more than one order of magnitude larger than that of bulk BaTiO3 crystal. The mechanism of the enhancement of the second-order optical non-linearity was discussed by taking into account the stress-induced lattice distortion and polarization enhancement.

关键词： BaTiO3/SrTiO3 superlattices laser molecular-beam epitaxy reflection high-energy electron diffrac-tion lattice misfit second-order optical nonlinearity.

Evolution of interfacial dislocation networks during long term thermal aging in Ni-based single crystal superalloy DD5

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China Foundry 2019年第1期16卷 14-22页

作者： Qiang Gao Li-rong Liu Xiao-hua Tang Zhi-jiang Peng Ming-jun Zhang Su-gui Tian School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China AECC Shenyang Liming Aero Engine Co.Ltd. Shenyang 110043China

Interfacial dislocations found in single crystal superalloys after long term thermal aging have an important effect on mechanical properties. Long term thermal aging tests for DD5 single crystal superalloy were carried out at 1,100 ℃ for 20, 100, 200, 500 and 1000 h, and then cooled by air. The effect of long term thermal aging on the dislocation networks at the γ/γ' interfaces was investigated by FE-SEM. Results showed that during the long term thermal aging at 1,100 ℃, misfit dislocations formed firstly and then reorientation in the(001) interfacial planes occurred. Different types of square or rectangular dislocation network form by dislocation reaction. Square dislocation networks consisting of four groups of dislocations can transform into octagonal dislocation networks, and then form another square dislocation network by dislocation reaction. Rectangular dislocation networks can also transform into hexagonal dislocation networks. The interfacial dislocation networks promote the γ' phase rafting process. The dislocation networks spacings become smaller and smaller, leading to the effective lattice misfit increasing from-0.10% to-0.32%.

关键词： DD5 single crystal superalloy interfacial dislocations long term thermal aging effective lattice misfit

THEORETIC CALCULATION OF SPECIFIC ENERGY OF SEMICOHERENT INTERFACE BETWEEN MICROALLOY CARBONITRIDE AND FERRITE

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Chinese Science Bulletin 1989年第20期34卷 1747-1751页

作者：雍岐龙李永福孙珍宝吴宝榕 Department of Mechanical Engineering Yunnan Institute of Technology Kunming Department of Alloy Steels Central Iron and Steel Research Institute Beijing

In some research of microalloy steel, such as the precipitation behaviour and the precipitation strengthening of microalloy carbonitride (M(CN)phase)in ferrite, it is essential to know the accurate value of the interfacial energy between M(CN )phase and ferrite. However, this energy cannot be directly measured because the average size of M(CN) particle is only 2-10 nm, thus the deepgoing researches concerned are seriously limited.

关键词： interfacial energy microalloy carbonitride misfit dislocation semicoherent interface