Secondary grain-boundary dislocations in (001) twist boundaries in MgO. I. Intrinsic structures

Technical Report · Tue Dec 01 00:00:00 EST 1981

OSTI ID:5265100

Sun, C P; Balluffi, R W

Intrinsic secondary grain boundary dislocation (GBD) structures were observed by weak beam transmission electron microscopy in a variety of (001) twist boundaries in MgO prepared by a welding technique. Square networks of intrinsic screw GBDs were found in boundaries possessing twist deviations from the exact = 1, 5, 13, 17, 25, 29 and 53 Coincidence Site Lattice (CSL) misorientations. ( = fraction of lattice sites in coincidence). These GBDs were all perfect GBDs with Burgers vectors given by the primitive vectors of the corresponding DSC-Lattice except in the case of = 13 where a square array of partial screw GBDs was observed. Arrays of screw GBDs were not detected in a number of high boundaries. Super-imposed arrays of edge type intrinsic GBDs were observed in all boundaries when a small tilt component was present.

• Research Organization: Massachusetts Inst. of Tech., Cambridge (USA). Dept. of Materials Science and Engineering
• DOE Contract Number: AS02-78ER05002
• OSTI ID: 5265100
• Report Number(s): DOE/ER/05002-24; ON: DE82007798
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
MAGNESIUM OXIDES
DISLOCATIONS
GRAIN BOUNDARIES
TRANSMISSION ELECTRON MICROSCOPY
ALKALINE EARTH METAL COMPOUNDS
CHALCOGENIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
LINE DEFECTS
MAGNESIUM COMPOUNDS
MICROSCOPY
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
360202* - Ceramics
Cermets
& Refractories- Structure & Phase Studies