TEM in situ deformation study of the interaction of lattice dislocations with grain boundaries in metals
- Materials Research Lab., Urbana, IL (United States)
The passage of dislocations across grain boundaries in metals has been studied by using the in situ TEM deformation technique. A detailed analysis of the interaction of glissile matrix dislocations with grain-boundary dislocations has been performed. The results show that the dislocations piled-up at the grain boundary can: (1) be transferred directly through the grain boundary into the adjoining grain; (2) be absorbed and transformed into extrinsic grain-boundary dislocations; (3) be accommodated in the grain boundary, followed by the emission from the grain boundary of a matrix dislocation; and (4) be ejected back into their original grain. To predict which slip system is favorable for slip transfer, three criteria have been considered, namely: (1) the angle between the lines of intersection of the incoming and outgoing slip lanes with the grain boundary, this should be as small as possible; (2) the resolved shear stress acting on the possible slip systems in the adjoining grain, this should be large and (3) the magnitude of the Burgers vector of the extrinsic dislocations left at the grain boundary following emission of dislocations, this should be a minimum. The Burgers vector of the generated dislocation is dictated primarily by condition (3).
- DOE Contract Number:
- AC02-76ER01198
- OSTI ID:
- 7163799
- Journal Information:
- Philosophical Magazine A. Defects and Mechanical Properties; (United Kingdom), Vol. 62:1; ISSN 0141-8610
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
ALLOYS
DISLOCATIONS
TRANSMISSION ELECTRON MICROSCOPY
METALS
BURGERS VECTOR
DEFORMATION
GRAIN BOUNDARIES
MILLER INDICES
STAINLESS STEELS
TITANIUM
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
ELEMENTS
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
LINE DEFECTS
MICROSCOPY
MICROSTRUCTURE
STEELS
TRANSITION ELEMENTS
400102* - Chemical & Spectral Procedures
360102 - Metals & Alloys- Structure & Phase Studies