Processing and Microstructural Characterization of TiB2 Liquid Phase Sintered with Ni and Ni3Al

1983 ◽  
Vol 24 ◽  
Author(s):  
P. Angelini ◽  
P. F. Becher ◽  
J. Bentley ◽  
C. B. Finch ◽  
P. S. Sklad
Keyword(s):  
Analytical Electron Microscopy ◽  
Phase Diagram Data ◽  
Microstructural Characterization ◽  
Convergent Beam Electron Diffraction ◽  
Intergranular Phase ◽  
X Ray ◽  
Analytical Electron ◽  
Convergent Beam ◽  
Electron Energy Loss

ABSTRACTAn Analytical Electron Microscopy investigation of TiB2 hot-pressed and pressureless sintered with Ni revealed the presence of Ni3B and tau intergranular phase, respectively. Convergent Beam Electron Diffraction (CBED) was used for crystal structure determination and compositions were determined by quantitative x-ray Energy Dispersive Spectroscopy (EDS) and Electron Energy Loss Spectroscopy (EELS). The phase analyses were compared with phase diagram data. An evaluation was also made of TiB2 hot pressed with Ni3Al. Quantitative EDS and EELS microanalysis indicated a Ni,Al type boride tau (Cr23C6 type) intergranular phase.

AEM Study of thin and Thick Film Metallization on AIN Substrates

1987 ◽  
Vol 108 ◽  
Author(s):  
Alistair D. Westwood ◽  
Michael R. Notis
Keyword(s):  
Electron Microscopy ◽  
Thick Film ◽  
Analytical Electron Microscopy ◽  
Microstructural Characterization ◽  
Convergent Beam Electron Diffraction ◽  
Transmission Electron ◽  
Analytical Electron ◽  
Convergent Beam ◽  
Boundary Penetration

ABSTRACTMicrostructural characterization of thin film (Au-Pt-Ti) and thick film (Mo-Mn) metallization on AIN substrates has been performed using Transmission Electron Microscopy (TEM), Analytical Electron Microscopy (AEM), Convergent Beam Electron Diffraction (CBED) and Auger Electron Spectroscopy (AES). The reaction mechanisms for both types of metallization methods are proposed. In particular, the microchemical and morphological nature of grain boundary penetration and precipitation within the AIN near the metallization interface has been examined.

Comparison of Performance of an Analytical Electron Microscope at 300 and 100 kV

1984 ◽  
Vol 41 ◽  
Author(s):  
J. Bentley ◽  
E. A. Kenik ◽  
P. Angelini ◽  
A. T. Fisher ◽  
P. S. Sklad ◽  
...  
Keyword(s):  
Electron Microscope ◽  
Materials Science ◽  
Convergent Beam Electron Diffraction ◽  
Beam Electron ◽  
X Ray ◽  
Transmission Electron ◽  
Analytical Electron ◽  
Analytical Electron Microscope ◽  
Convergent Beam ◽  
Electron Energy Loss

AbstractPreliminary results on the performance of an analytical electron microscope (AEM) operating at 300 kV have been obtained and compared with the performance at 100 kV. Some features of the anticipated improvements for transmission electron microscopy (TEM) imaging, convergent beam electron diffraction (CBED), energy dispersive X-ray spectroscopy (EDS), and electron energy loss spectroscopy (EELS) have been studied from the aspect of materials science applications. The electron microscope used was a Philips EM430T operated with a LaB6 cathode and equipped with EDAX 9100/70 EDS and Gatan 607 EELS systems.

Secondary fluorescence effects on x-ray microanalysis

1984 ◽  
Vol 42 ◽  
pp. 582-583
Author(s):  
P. Angelini ◽  
J. Bentley
Keyword(s):  
Electron Microscopy ◽  
Analytical Electron Microscopy ◽  
Phase Diagram Data ◽  
Intergranular Phase ◽  
X Ray ◽  
Analytical Electron ◽  
Sintering Mechanisms ◽  
Line Compound ◽  
Ti Content ◽  
Secondary Fluorescence

The structure and composition of intergranular phases present in TiB2 hotpressed or sintered with Ni additive are being analyzed to evaluate sintering mechanisms. Analytical electron microscopy (AEM) has shown that the major intergranular phase present in TiB2 hot-pressed with Ni is Ni3B, but in TiB2 sintered with Ni is a boride tau phase. Energy dispersive x-ray spectroscopy (EDS) of the intergranular Ni3B indicated a Ti content of ∼8 at. % (all compositions quoted are normalized where at. % Ti + at. % Ni = 100%). However, phase diagram data show Ni3B to be a line compound with limited Ti solubility. The present experiments were performed to assess the suspected influence of secondary fluorescence effects on EDS analyses.

A library of convergent-beam electron diffraction patterns

1986 ◽  
Vol 44 ◽  
pp. 688-691
Author(s):  
John F. Mansfield
Keyword(s):  
Electron Diffraction ◽  
Materials Science ◽  
Convergent Beam Electron Diffraction ◽  
Beam Electron ◽  
Transmission Electron ◽  
Yield Information ◽  
Analytical Electron ◽  
Diffraction Patterns ◽  
Convergent Beam ◽  
Electron Energy Loss

One of the most important advancements of the transmission electron microscopy (TEM) in recent years has been the development of the analytical electron microscope (AEM). The microanalytical capabilities of AEMs are based on the three major techniques that have been refined in the last decade or so, namely, Convergent Beam Electron Diffraction (CBED), X-ray Energy Dispersive Spectroscopy (XEDS) and Electron Energy Loss Spectroscopy (EELS). Each of these techniques can yield information on the specimen under study that is not obtainable by any other means. However, it is when they are used in concert that they are most powerful. The application of CBED in materials science is not restricted to microanalysis. However, this is the area where it is most frequently employed. It is used specifically to the identification of the lattice-type, point and space group of phases present within a sample. The addition of chemical/elemental information from XEDS or EELS spectra to the diffraction data usually allows unique identification of a phase.

Phase identification in SiC whisker reinforced Al2O3-R2O3-based composites

1992 ◽  
Vol 50 (1) ◽  
pp. 152-153
Author(s):  
C.M. Sung ◽  
K.J. Ostreicher ◽  
M.L. Huckabee ◽  
S.T. Buljan
Keyword(s):  
Analytical Electron Microscopy ◽  
Phase Identification ◽  
Reinforced Composites ◽  
Ion Milling ◽  
X Ray ◽  
Binary Oxides ◽  
Analytical Electron ◽  
The Matrix ◽  
Second Phases ◽  
Convergent Beam

A series of binary oxides and SiC whisker reinforced composites both having a matrix composed of an α-(Al, R)2O3 solid solution (R: rare earth) have been studied by analytical electron microscopy (AEM). The mechanical properties of the composites as well as crystal structure, composition, and defects of both second phases and the matrix were investigated. The formation of various second phases, e.g. garnet, β-Alumina, or perovskite structures in the binary Al2O3-R2O3 and the ternary Al2O3-R2O3-SiC(w) systems are discussed.Sections of the materials having thicknesses of 100 μm - 300 μm were first diamond core drilled. The discs were then polished and dimpled. The final step was ion milling with Ar+ until breakthrough occurred. Samples prepared in this manner were then analyzed using the Philips EM400T AEM. The low-Z energy dispersive X-ray spectroscopy (EDXS) data were obtained and correlated with convergent beam electron diffraction (CBED) patterns to identify phase compositions and structures. The following EDXS parameters were maintained in the analyzed areas: accelerating voltage of 120 keV, sample tilt of 12° and 20% dead time.

scholarly journals Microstructural Characterization of Multiphase Coatings Produced By Chemical Vapor Deposition

1989 ◽  
Vol 168 ◽  
Author(s):  
R. A. Lowden ◽  
K. L. More ◽  
T. M. Besmann ◽  
R. D. James
Keyword(s):  
Chemical Vapor Deposition ◽  
Vapor Deposition ◽  
Analytical Electron Microscopy ◽  
Chemical Vapor ◽  
Microstructural Characterization ◽  
X Ray Diffraction ◽  
Experimental Conditions ◽  
Analytical Electron ◽  
Scanning Transmission

AbstractChemical vapor deposition has been utilized to produce ternary, multiphase coatings of various compositions of silicon carbide (SiC) with Ti, Cr, and Mo. Thermodynamic calculations have been performed for a variety of experimental conditions in each system. Scanning, transmission and analytical electron microscopy, and X-ray diffraction techniques have been used to characterize the microstructures and to determine compositions.

Characterization of Si(Li) x-ray detector efficiencies in the low energy range

1986 ◽  
Vol 44 ◽  
pp. 710-711
Author(s):  
G. Wirmark ◽  
G. Wahlberg ◽  
H. Nordén
Keyword(s):  
Thin Film ◽  
Electron Microscopy ◽  
Energy Range ◽  
Analytical Electron Microscopy ◽  
Low Energy ◽  
Ratio Method ◽  
X Ray ◽  
Standard Specimens ◽  
Analytical Electron

X-ray microanalysis with windowless or ultra-thin window Si(Li)-detectors is becoming increasingly important in analytical electron microscopy. The most common approach in the quantification of this method is the thin film ratio method.where CA and CB denote the concentrations of elements A and B respectively and IA and IB are the corresponding x-ray intensities. The KAB-factor should ideally be determined from analyses of standard specimens of known compositions.

Characterization of iron-implanted silicon carbide

1992 ◽  
Vol 50 (1) ◽  
pp. 346-347
Author(s):  
J. Bentley ◽  
L. J. Romana ◽  
L. L. Horton ◽  
C. J. McHargue
Keyword(s):  
Silicon Carbide ◽  
Analytical Electron Microscopy ◽  
Implant Surface ◽  
Convergent Beam ◽  
Amorphous Sic ◽  
Iron Profile ◽  
Electron Energy Loss ◽  
Crystalline Forms ◽  
Fe Ions

As part of extensive fundamental studies of ion-implanted ceramics, analytical electron microscopy (AEM) has been used to characterize [0001] single crystal 6H α-silicon carbide implanted at room temperature with 160 keV 57Fe ions to fluences of 1,3, and 6 x 1016 ions/cm2. AEM was performed at 100 kV with a Philips EM400T equipped with a field emission gun, a 6585 STEM unit, an EDAX 9100/70 energy dispersive X-ray spectrometer (EDS), and a Gatan 666 parallel-detection electron energy loss spectrometer (PEELS).A micrograph of a cross-sectioned specimen implanted with 6 × 1016 ions/cm2 is shown in Fig. 1. The implanted region extending to 195 nm from the surface is amorphous, as confirmed by convergent beam electron diffraction (CBED) patterns (insets), and contains iron at levels easily detectable by EDS (Fig. 2). The 15 nm lattice fringes of the edge-on 6H basal planes in the substrate provide an unambiguous depth calibration scale. The transition layer at the end of the ion range exhibits the expected strain contrast. The depth profile of the implanted iron was measured by EDS line scans perpendicular to the implant surface; the mean of three of these scans is shown by the filled symbols in Fig. 3. The integrated iron profile agrees with the expected 6.0 × 1016 ions/cm2 only if the density of the amorphous SiC is equal to that of its crystalline forms, rather than the 20% lower density reported earlier.

Advantages of FE-TEM for convergent-beam electron diffraction

1993 ◽  
Vol 51 ◽  
pp. 1206-1207
Author(s):  
T. Kaneyama ◽  
T. Tomita ◽  
Y. Ishida ◽  
M. Kersker
Keyword(s):  
Electron Diffraction ◽  
Spatial Resolution ◽  
Convergent Beam Electron Diffraction ◽  
Lens System ◽  
Beam Electron ◽  
X Ray ◽  
Small Probe ◽  
Electron Microscopes ◽  
Convergent Beam ◽  
Electron Energy Loss

Many electron microscopes equipped with a field-emission gun (FE-TEMs) are now used for the purpose of improving the spatial and the energy resolution in energy dispersive x-ray spectroscopy and electron energy loss spectroscopy. For the convergent-beam electron diffraction techniques, FE-TEMs have greater advantages than conventional electron microscopes with a thermal LaB cathode. We discussed these advantages using JEM2010F and JEM2010, which have equivalent specifications except for the electron source and the condenser lens system.High spatial resolutionThe brightness of an FE-gun (∽ 5 × 108A cm-2 sr-1) is about 100 times that a conventional LaB6 cathode. The gun can obtain enough current for taking CBED patterns in an exposure time of a few seconds even with an electron probe less than 1 nm in diameter (FIG. 1). Steep wedge shapes and rapid bends within the illuminated area deteriorate the accuracy of quantitative CBED analysis. Improvement of the spatial resolution by a small probe reduces these inevitable averaging effects.

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