Lattice Image and Optical Diffraction Studies of Alloys

Conference · Mon Mar 01 04:00:00 EST 1976

OSTI ID:7149152

Thomas, G. ^[1]; Sinclair, R. ^[1]; Gronsky, R. ^[1]

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1. Lawrence Berkeley Laboratory (LBL), Berkeley, CA (United States); University of California, Berkeley, CA (United States)

Progress in applying lattice imaging to problems in alloys at the atomic level is reviewed. This has been illustrated by results on unit cell high steps in interfaces in ordered Mg/sub 3/Cd, on direct and reciprocal space studies of spinodal decomposition in Au-Ni and on grain boundary precipitation in Al-Zn. These observations, at present, are unique in the metallurgical field. Direct images have been complemented by optical diffraction patterns, with the possibility of using selecting apertures down to 10A in diameter, which is a considerable reduction over conventional electron diffraction. Such apertures are also smaller than areas currently selected by the beam size in scanning transmission electron microscopy. The microdiffraction capability is being used to solve ambiguous, conventional diffraction patterns, such as those obtained from short-range ordered alloys, and for more complex patterns, as for instance obtained from ordered stacking structures in SiC. The optical patterns from larger areas are also compared with the original electron diffraction patterns to ensure that the lattice image contains the pertinent information of the specimen lattice. It is noted that lattice imaging is assuming an important role in studying fundamental aspects of materials science.

• Research Organization: University of California, Berkeley, CA (United States); Lawrence Berkeley Laboratory (LBL), Berkeley, CA (United States)
• Sponsoring Organization: US Energy Research and Development Administration (ERDA); National Science Foundation (NSF)
• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 7149152
• Report Number(s): LBL--4962; CONF-760928-2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOY SYSTEMS
ALLOYS
ALUMINIUM ALLOYS
BINARY ALLOY SYSTEMS
CADMIUM ALLOYS
COHERENT SCATTERING
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRON DIFFRACTION
ELECTRON MICROSCOPY
GOLD ALLOYS
GRAIN BOUNDARIES
HARDENING
IMAGES
INTERMETALLIC COMPOUNDS
MAGNESIUM ALLOYS
MICROSCOPY
MICROSTRUCTURE
NICKEL ALLOYS
ORDER PARAMETERS
PHASE TRANSFORMATIONS
PRECIPITATION HARDENING
SCATTERING
ZINC ALLOYS