Deformation and microstructure of rutile

Studies of the mechanical properties of rutiles are described, in particular the behaviour of the elastic limit under compression with respect to variations in temperature (pure rutile), intrinsic non-stoichiometry (pure rutile reduced under low oxygen pressure) and extrinsic non-stoichiometry (rutile doped with chromia and alumina). A wide range of values is obtained, which may be understood in terms of the interaction of dislocations belonging to the slip systems {101} <1̄01> and {110} <001> with impurities, non-stoichiometric small and extended defects and precipitates. Transmission electron microscopy at medium resolution as well as high-resolution electron microscopy have been used to relate mechanical behaviour with microstructure.

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Microstructure of Extremely Fine Lamellae in a TiAl Base Alloy Studied by High-resolution Electron Microscopy

MRS Proceedings ◽

10.1557/proc-400-281 ◽

1995 ◽

Vol 400 ◽

Cited By ~ 1

Author(s):

E. Abe ◽

T. Kumagai ◽

M. Nakamura

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Base Alloy ◽

High Resolution Electron Microscopy ◽

Thin Plates ◽

Al Alloy ◽

Transmission Electron ◽

Resolution Electron ◽

Wide Range ◽

Ice Water

AbstractAn extremely fine lamellar structure formed in a Ti-48at.%Al alloy, which was heat treated in the high-temperature α-Ti (disordered hcp) single phase field (1683K), followed by ice water quenching, has been examined by high-resolution and analytical transmission electron microscopy. The microstracture consists of thin plates of ordered α2-Ti3Al (D019: ordered version of hcp) and γ-TiAl (Ll0: ordered version of fcc) phases, and interfaces of lamellae are atomically flat in a wide range. From detailed analyses of the microstructure and composition in nm scale, the α→γ phase transformation, which occurs during quenching and produces the extremely fine α2-γ lamellae, has been discussed.

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Recent Applications of High Resolution Electron Microscopy to Crystalline Arrays of Virus Particles

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070199 ◽

1978 ◽

Vol 36 (3) ◽

pp. 470-482 ◽

Cited By ~ 1

Author(s):

R.W. Horne

Keyword(s):

Electron Microscopy ◽

Image Processing ◽

Analytical Techniques ◽

Staining Technique ◽

High Resolution Electron Microscopy ◽

Optical Diffraction ◽

Full Potential ◽

Virus Particles ◽

Resolution Electron ◽

Wide Range

The technique of surrounding virus particles with a neutralised electron dense stain was described at the Fourth International Congress on Electron Microscopy, Berlin 1958 (see Home & Brenner, 1960, p. 625). For many years the negative staining technique in one form or another, has been applied to a wide range of biological materials. However, the full potential of the method has only recently been explored following the development and applications of optical diffraction and computer image analytical techniques to electron micrographs (cf. De Hosier & Klug, 1968; Markham 1968; Crowther et al., 1970; Home & Markham, 1973; Klug & Berger, 1974; Crowther & Klug, 1975). These image processing procedures have allowed a more precise and quantitative approach to be made concerning the interpretation, measurement and reconstruction of repeating features in certain biological systems.

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Interface structures in polycrystalline ceramic materials

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100143900 ◽

1986 ◽

Vol 44 ◽

pp. 468-471

Author(s):

K. J. Morrissey

Keyword(s):

Electron Microscopy ◽

Analytical Electron Microscopy ◽

Physical And Mechanical Properties ◽

High Resolution Electron Microscopy ◽

Ceramic Materials ◽

Polycrystalline Materials ◽

Transmission Electron ◽

Resolution Electron ◽

Interface Structures

Grain boundaries and interfaces play an important role in determining both physical and mechanical properties of polycrystalline materials. To understand how the structure of interfaces can be controlled to optimize properties, it is necessary to understand and be able to predict their crystal chemistry. Transmission electron microscopy (TEM), analytical electron microscopy (AEM,), and high resolution electron microscopy (HREM) are essential tools for the characterization of the different types of interfaces which exist in ceramic systems. The purpose of this paper is to illustrate some specific areas in which understanding interface structure is important. Interfaces in sintered bodies, materials produced through phase transformation and electronic packaging are discussed.

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High Resolution Transmission Electron Microscopy of an automobile catalytic converter

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100174345 ◽

1990 ◽

Vol 48 (4) ◽

pp. 242-243

Author(s):

Jan-Olle Malm ◽

Jan-Olov Bovin

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Catalytic Converter ◽

Active Material ◽

Image Intensifier ◽

High Resolution Electron Microscopy ◽

Detailed Knowledge ◽

Transmission Electron ◽

Resolution Electron ◽

Atomic Surface

Understanding of catalytic processes requires detailed knowledge of the catalyst. As heterogeneous catalysis is a surface phenomena the understanding of the atomic surface structure of both the active material and the support material is of utmost importance. This work is a high resolution electron microscopy (HREM) study of different phases found in a used automobile catalytic converter.The high resolution micrographs were obtained with a JEM-4000EX working with a structural resolution better than 0.17 nm and equipped with a Gatan 622 TV-camera with an image intensifier. Some work (e.g. EDS-analysis and diffraction) was done with a JEM-2000FX equipped with a Link AN10000 EDX spectrometer. The catalytic converter in this study has been used under normal driving conditions for several years and has also been poisoned by using leaded fuel. To prepare the sample, parts of the monolith were crushed, dispersed in methanol and a drop of the dispersion was placed on the holey carbon grid.

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Transmission electron microscopy observation in a liquid-phase-sintered SiC with oxynitride glass

Journal of Materials Research ◽

10.1557/jmr.2001.0299 ◽

2001 ◽

Vol 16 (8) ◽

pp. 2189-2191 ◽

Cited By ~ 1

Author(s):

Guo-Dong Zhan ◽

Mamoru Mitomo ◽

Young-Wook Kim ◽

Rong-Jun Xie ◽

Amiya K Mukherjee

Keyword(s):

Electron Microscopy ◽

Liquid Phase ◽

High Resolution Electron Microscopy ◽

Nitrogen Atmosphere ◽

X Ray Diffraction ◽

Sintering Additive ◽

Transmission Electron ◽

High Annealing ◽

Resolution Electron ◽

Oxynitride Glass

Using a pure α–SiC starting powder and an oxynitride glass composition from the Y–Mg–Si–Al–O–N system as a sintering additive, a powder mixture was hot-pressed at 1850 °C for 1 h under a pressure of 20 MPa and further annealed at 2000 °C for 4 h in a nitrogen atmosphere of 0.1 MPa. High-resolution electron microscopy and x-ray diffraction studies confirmed that a small amount of β–SiC was observed in the liquid-phase-sintered α–SiC with this oxynitride glass, indicating stability of β–SiC even at high annealing temperature, due to the nitrogen-containing liquid phase.

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Structure of InAs Quantum Dots in Si Matrix Investigated by High Resolution Electron Microscopy

MRS Proceedings ◽

10.1557/proc-571-299 ◽

1999 ◽

Vol 571 ◽

Cited By ~ 1

Author(s):

N. D. Zakharov ◽

P. Werner ◽

V. M. Ustinov ◽

A.R. Kovsh ◽

G. E. Cirlin ◽

...

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Critical Thickness ◽

High Resolution Electron Microscopy ◽

Geometrical Parameters ◽

Inas Quantum Dots ◽

Temperature Growth ◽

Transmission Electron ◽

Resolution Electron

ABSTRACTQuantum dot structures containing 2 and 7 layers of small coherent InAs clusters embedded into a Si single crystal matrix were grown by MBE. The structure of these clusters was investigated by high resolution transmission electron microscopy. The crystallographic quality of the structure severely depends on the substrate temperature, growth sequence, and the geometrical parameters of the sample. The investigation demonstrates that Si can incorporate a limited volume of InAs in a form of small coherent clusters about 3 nm in diameter. If the deposited InAs layer exceeds a critical thickness, large dislocated InAs precipitates are formed during Si overgrowth accumulating the excess of InAs.

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Silicon-Sapphire Interface: A High Resolution Electron Microscopy Study

MRS Proceedings ◽

10.1557/proc-2-285 ◽

1980 ◽

Vol 2 ◽

Cited By ~ 1

Author(s):

Fernando A. Ponce

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Silicon Layer ◽

High Resolution Electron Microscopy ◽

Microscopy Study ◽

Electron Microscopy Study ◽

Resolution Limit ◽

High Concentration ◽

Transmission Electron ◽

Resolution Electron

ABSTRACTThe structure of the silicon-sapphire interface of CVD silicon on a (1102) sapphire substrate has been studied in crøss section by high resolution transmission electron microscopy. Multibeam images of the interface region have been obtained where both the silicon and sapphire lattices are directly resolved. The interface is observed to be planar and abrupt to the instrument resolution limit of 3 Å. No interfacial phase is evident. Defects are inhomogeneously distributed at the interface: relatively defect-free regions are observed in the silicon layer in addition to regions with high concentration of defects.

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Structure, Composition and Stability of Heterophase Boundaries

Microscopy and Microanalysis ◽

10.1017/s1431927600010254 ◽

1997 ◽

Vol 3 (S2) ◽

pp. 673-674

Author(s):

M. Rühle ◽

T. Wagner ◽

S. Bernath ◽

J. Plitzko ◽

C. Scheu ◽

...

Keyword(s):

Electron Microscopy ◽

Elevated Temperatures ◽

Analytical Electron Microscopy ◽

High Resolution Electron Microscopy ◽

Advanced Materials ◽

Bulk Crystals ◽

Transmission Electron ◽

Resolution Electron ◽

The Stability

Heterophase boundaries play an important role in advanced materials since those materials often comprise different components. The properties of the materials depend strongly on the properties of the interface between the components. Thus, it is important to investigate the stability of the microstructure with respect to annealing at elevated temperatures. In this paper results will be presented on the structure and composition of the interfaces between Cu and (α -Al2O3. The interfaces were processed either by growing a thin Cu overlayer on α- Al2O3 in a molecular beam epitaxy (MBE) system or by diffusion bonding bulk crystals of the two constituents in an UHV chamber. To improve the adhesion of Cu to α -Al2O3 ultrathin Ti interlayers were deposited between Cu and α - Al2O3.Interfaces were characterized by different transmission electron microscopy (TEM) techniques. Quantitative high-resolution electron microscopy (QHRTEM) allows the determination of the structure (coordinates of atoms) while analytical electron microscopy (AEM) allows the determination of the composition with high spatial resolution.

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Phase Diagram Determination For Modifications Of The D Phase In The Al-AlCo-AINi System

MRS Proceedings ◽

10.1557/proc-553-25 ◽

1998 ◽

Vol 553 ◽

Cited By ~ 15

Author(s):

R. Lück ◽

M. Scheffer ◽

T. Gödecke ◽

S. Ritschj ◽

C. Beelif

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Liquidus Projection ◽

High Resolution Electron Microscopy ◽

Reaction Scheme ◽

Decagonal Phase ◽

Transmission Electron ◽

Resolution Electron ◽

In Situ Experiments ◽

Projection Surface

AbstractAn extensive investigation into the At-AICo-AlNi ternary subsystem is presented. Observations have used the techniques of differential thermal analysis, magnetothermal analysis, dilatometry, metallography, X-ray diffraction, transmission electron microscopy, and high-resolution electron microscopy. Representative graphic documentation, as liquidus projection surface, isothermal sections, temperature-concentration section, and reaction scheme are presented. 11 phases from the binaries Al-Co and Al-Ni and the three ternary phases Y2 (Co2NiAl9), X and the decagonal phase D were found at room temperature. The decagonal phase is formed from the melt peritectically via a critical tie line and its primary formation area dominates at the liquidus projection surface. 45 three-phase regions are present according to the reaction scheme.Several phase variants in the area of the decagonal phase were detected by transmission electron microscopy. Phase fields of the variants were determined from samples quenched from their respective temperatures. In-situ experiments on transformations of variants were performed by dilatometric measurements. The subdivision of the D phase area into the fields of the variants is discussed.

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