Revealing the influence of crystallographic orientation on the electrochemical and discharge behaviors of extruded diluted Mg–Sn–Zn–Ca alloy as anode for Mg-air battery

The increasing availability of synchrotron x-ray sources has stimulated the development of advanced hard x-ray (E≥5 keV) microprobes. With new x-ray optics these microprobes can achieve micron and submicron spatial resolutions. The inherent elemental and crystallographic sensitivity of an x-ray microprobe and its inherently nondestructive and penetrating nature will have important applications to materials science. For example, x-ray fluorescent microanalysis of materials can reveal elemental distributions with greater sensitivity than alternative nondestructive probes. In materials, segregation and nonuniform distributions are the rule rather than the exception. Common interfaces to whichsegregation occurs are surfaces, grain and precipitate boundaries, dislocations, and surfaces formed by defects such as vacancy and interstitial configurations. In addition to chemical information, an x-ray diffraction microprobe can reveal the local structure of a material by detecting its phase, crystallographic orientation and strain.Demonstration experiments have already exploited the penetrating nature of an x-ray microprobe and its inherent elemental sensitivity to provide new information about elemental distributions in novel materials.

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Texture measurements in Al2O3 using BEKP

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170773 ◽

1994 ◽

Vol 52 ◽

pp. 608-609

Author(s):

M. D. Vaudin ◽

J. P. Cline

Keyword(s):

Neutron Diffraction ◽

Rapid Method ◽

Crystallographic Orientation ◽

Specimen Surface ◽

X Ray Diffraction ◽

Anisotropic Crystal ◽

X Ray ◽

Verification Method ◽

Crystal Properties ◽

Backscattered Electron

The study of preferred crystallographic orientation (texture) in ceramics is assuming greater importance as their anisotropic crystal properties are being used to advantage in an increasing number of applications. The quantification of texture by a reliable and rapid method is required. Analysis of backscattered electron Kikuchi patterns (BEKPs) can be used to provide the crystallographic orientation of as many grains as time and resources allow. The technique is relatively slow, particularly for noncubic materials, but the data are more accurate than any comparable technique when a sufficient number of grains are analyzed. Thus, BEKP is well-suited as a verification method for data obtained in faster ways, such as x-ray or neutron diffraction. We have compared texture data obtained using BEKP, x-ray diffraction and neutron diffraction. Alumina specimens displaying differing levels of axisymmetric (0001) texture normal to the specimen surface were investigated.BEKP patterns were obtained from about a hundred grains selected at random in each specimen.

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Preparation of integrated circuits for TEM electromigration in situ studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100145753 ◽

1986 ◽

Vol 44 ◽

pp. 882-883

Author(s):

J. V. Maskowitz ◽

W. E. Rhoden ◽

D. R. Kitchen ◽

R. E. Omlor ◽

P. F. Lloyd

Keyword(s):

Integrated Circuits ◽

Crystallographic Orientation ◽

Silicon Wafers ◽

Minimum Size ◽

Test Vehicle ◽

In Situ Studies ◽

Boron Doped ◽

Doped Silicon ◽

Drill Holes

The fabrication of the aluminum bridge test vehicle for use in the crystallographic studies of electromigration involves several photolithographic processes, some common, while others quite unique. It is most important to start with a clean wafer of known orientation. The wafers used are 7 mil thick boron doped silicon. The diameter of the wafer is 1.5 inches with a resistivity of 10-20 ohm-cm. The crystallographic orientation is (111).Initial attempts were made to both drill and laser holes in the silicon wafers then back fill with photoresist or mounting wax. A diamond tipped dentist burr was used to successfully drill holes in the wafer. This proved unacceptable in that the perimeter of the hole was cracked and chipped. Additionally, the minimum size hole realizable was > 300 μm. The drilled holes could not be arrayed on the wafer to any extent because the wafer would not stand up to the stress of multiple drilling.

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