Analytical Electron Microscopy Studies of Bi-Substituted Garnet Films

1991 ◽  
Vol 232 ◽  
Author(s):  
P. A. Crozier ◽  
P. A. Labun ◽  
T Suzuki
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Second Phase ◽  
Processing Conditions ◽  
Transformation Kinetics ◽  
Heating Rates ◽  
Garnet Films ◽  
Analytical Electron ◽  
In Situ Heating

ABSTRACTIn-situ heating in an electron microscope, together with EDX and EELS analysis, was used to characterize as-deposited amorphous and transformed garnet films. It was found that upon initial crystallization, a non-uniform precipitation of a second phase occurred, altering the local chemistry and microstructure of the transformed film. In addition, to study the transformation kinetics in more detail some experiments were conducted at slower heating rates and lower temperatures. It is hoped that the data obtained can be correlated to magnetic property measurements and contribute to the development of improved processing conditions.

Application of analytical electron microscopy to the study of partitioning of silicon in a 2 wt% Si eutectoid steel

1978 ◽  
Vol 36 (1) ◽  
pp. 616-617
Author(s):  
N. Ridley ◽  
S.A. Al-Salman ◽  
G.W. Lorimer
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Analytical Electron Microscopy ◽  
Eutectoid Steel ◽  
Minimum Diameter ◽  
Thin Foils ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Transformation Front

The application of the technique of analytical electron microscopy to the study of partitioning of Mn (1) and Cr (2) during the austenite-pearlite transformation in eutectoid steels has been described in previous papers. In both of these investigations, ‘in-situ’ analyses of individual cementite and ferrite plates in thin foils showed that the alloying elements partitioned preferentially to cementite at the transformation front at higher reaction temperatures. At lower temperatures partitioning did not occur and it was possible to identify a ‘no-partition’ temperature for each of the steels examined.In the present work partitioning during the pearlite transformation has been studied in a eutectoid steel containing 1.95 wt% Si. Measurements of pearlite interlamellar spacings showed, however, that except at the highest reaction temperatures the spacing would be too small to make the in-situ analysis of individual cementite plates possible, without interference from adjacent ferrite lamellae. The minimum diameter of the analysis probe on the instrument used, an EMMA-4 analytical electron microscope, was approximately 100 nm.

Analytical Electron Microscopy of Surface-Modified Ceramics

1985 ◽  
Vol 43 ◽  
pp. 276-279
Author(s):  
P. S. Sklad
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Theoretical Models ◽  
Ceramic Materials ◽  
Solute Concentration ◽  
Second Phase ◽  
Analytical Electron ◽  
Implantation Techniques ◽  
Lattice Damage ◽  
Surface Modified

Over the past several years, it has become increasingly evident that materials for proposed advanced energy systems will be required to operate at high temperatures and in aggressive environments. These constraints make structural ceramics attractive materials for these systems. However it is well known that the condition of the specimen surface of ceramic materials is often critical in controlling properties such as fracture toughness, oxidation resistance, and wear resistance. Ion implantation techniques offer the potential of overcoming some of the surface related limitations.While the effects of implantation on surface sensitive properties may be measured indpendently, it is important to understand the microstructural evolution leading to these changes. Analytical electron microscopy provides a useful tool for characterizing the microstructures produced in terms of solute concentration profiles, second phase formation, lattice damage, crystallinity of the implanted layer, and annealing behavior. Such analyses allow correlations to be made with theoretical models, property measurements, and results of complimentary techniques.

Grain Boundary Chemistry in Al-Cu Metallizations as Determined by Analytical Electron Microscopy

1991 ◽  
Vol 229 ◽  
Author(s):  
J. R. Michael ◽  
A. D. Romig ◽  
D. R. Frear
Keyword(s):  
Electron Microscopy ◽  
Integrated Circuits ◽  
Grain Boundary ◽  
Analytical Electron Microscopy ◽  
Second Phase ◽  
Collector Plate ◽  
Analytical Electron ◽  
Cu Thin Film ◽  
Boundary Chemistry ◽  
Interconnect Lines

AbstractAl with additions of Cu is commonly used as the conductor metallizations for integrated circuits (ICs). As the packing density of ICs increases, interconnect lines are required to carry ever higher current densities. Consequently, reliability due to electromigration failure becomes an increasing concern. Cu has been found to increase the lifetimes of these conductors, but the mechanism by which electromigration is improved is not yet fully understood. In order to evaluate certain theories of electromigration it is necessary to have a detailed description of the Cu distribution in the Al microstructure, with emphasis on the distribution of Cu at the grain boundaries. In this study analytical electron microscopy (AEM) has been used to characterize grain boundary regions in an Al-2 wt.% Cu thin film metallization on Si after a variety of thermal treatments. The results of this study indicate that the Cu distribution is dependent on the thermal annealing conditions. At temperatures near the θ phase (CuAl2) solvus, the Cu distribution may be modelled by the collector plate mechanism, in which the grain boundary is depleted in Cu relative to the matrix. At lower temperatures, Cu enrichment of the boundaries occurs, perhaps as a precursor to second phase formation. Natural cooling from the single phase field produces only grain boundary depletion of Cu consistent with the collector-plate mechanism. The kinetic details of the elemental segregation behavior derived from this study can be used to describe microstructural evolution in actual interconnect alloys.

Phase Identification in TiB2-Ni Composites by Analytical Electron Microscopy

1981 ◽  
Vol 39 ◽  
pp. 138-139
Author(s):  
P. S. Sklad ◽  
J. Bentley ◽  
A. T. Fisher ◽  
G. L. Lehman
Keyword(s):  
Electron Microscopy ◽  
Cutting Tools ◽  
Analytical Electron Microscopy ◽  
High Hardness ◽  
Phase Identification ◽  
Second Phase ◽  
Binder Phase ◽  
Ion Milling ◽  
X Ray ◽  
Analytical Electron

The transition metal diboride TiB2 is characterized by high hardness and high melting point (3253 K) . These properties make this material attractive for applications such as valve components in coal liquefaction plants and cutting tools. Liquid phase hot pressing using nickel as the fluidizing medium allows densification at lower temperatures than when using TiB2 powders alone, but the nickel and TiB2 react to form a complex multiphase microstructure. The purpose of this investigation was to identify the nickel-rich binder phase. The material examined was taken from a cylindrical compact hot pressed at ∼1720 K. During pressing most of the original 15 mol % Ni exuded from the initial mixtures. Specimens 3 mm dia were prepared for analytical electron microscopy (AEM) examination by mechanical lapping followed by ion milling.A typical microstructure of the TiB2-Ni composite examined at 120 kv by conventional transmission electron microscopy (TEM) is shown in Fig. 1. The microstructure is characterized by TiB2 grains bonded by a second phase which was observed at multiple grain intersections. X-ray energy dispersive spectroscopy (EDS) measurements were made using a Philips EM400T/FEG. probe sizes of ∼10 nm dia and probe currents of ∼5 nA were used so that measurements could be made in thin regions of the binder phase, where beam broadening was small. Typical x-ray spectra from an intergranular region and an adjacent TiB2 grain are shown in Fig. 2. The results of standardless quantitative analyses of binder phase spectra indicated a composition (for Z > 11) of at least 95% Ni.

In Situ PEEL Spectroscopic Determination and EFTEM Imaging of Multiple Materials Properties at the Nanoscale Using Universality and Scaling in Solid-State Property-Plasmon Energy Relationships: New Capabilities for Analytical Electron Microscopy

2004 ◽  
Vol 10 (S03) ◽  
pp. 56-57
Author(s):  
Vladimir P. Oleshko ◽  
James M. Howe
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Plasmon Energy ◽  
Materials Properties ◽  
Analytical Electron ◽  
Materials Research ◽  
Energy Relationships ◽  
Multiple Materials ◽  
Free Environment

Extended abstract of a paper presented at the Pre-Meeting Congress: Materials Research in an Aberration-Free Environment, at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, July 31 and August 1, 2004.

Growth of Lamellar Products During Discontinuous Solid State Reactions

1999 ◽  
Vol 580 ◽  
Author(s):  
P. Zieba ◽  
W. Gust
Keyword(s):  
Electron Microscopy ◽  
Solid State ◽  
Discontinuous Precipitation ◽  
Analytical Electron Microscopy ◽  
Morphological Features ◽  
Solid State Reactions ◽  
Analytical Electron ◽  
Nucleation Growth

AbstractThe nucleation, growth and dissolution of lamellar precipitates formed due to discontinuous solid state reactions like: discontinuous precipitation, coarsening and dissolution, are reviewed. Emphasis is given on recent studies based on analytical electron microscopy in describing the microchemistry, and in situ electron microscopy for revealing the morphological features of the reactions.

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