Core diffusion, unpinning and the Snoek-Koster relaxation

Journal Article · Fri Jan 01 04:00:00 EST 1982 · Scr. Metall.; (United States)

DOI:https://doi.org/10.1016/0036-9748(82)90344-1· OSTI ID:5947174

Ritchie, I G

The Snoek-Koster relaxation, S-K(X), involves the dragging of core mobile impurity interstitials (X) by dislocations in bcc metals. Experimental results are generally compared with the predictions of a model proposed by Schoeck, with varying degrees of success. It assumes the transverse drag of X atoms by dislocation segments that bow-out (under the influence of an applied stress of amplitude sigma) according to the vibrating string model of dislocation motion. The S-K relaxation is well established in bcc transition metals. It has been shown that similar phenomena occur in the hcp transition metals and argued that S-K-type relaxations should be general phenomena in deformed crystalline solids, where pinned dislocation configurations survive into regions of the T-epsilon plane, where some core mobility is possible. Both longitudinal (S-K') and transverse (S-K) core mobility should be taken into account, because the corresponding relaxations are interrelated. In some experimental conditions, the vibrating string model of Schoeck should be applicable; in others, where 2H/sub K/ is a significant fraction of H/sub SK/, the kink model of Seeger and Hirth should be invoked.

• Research Organization: White Shell Nuclear Research Establishment, Manitoba, Canada
• OSTI ID: 5947174
• Journal Information: Scr. Metall.; (United States), Journal Name: Scr. Metall.; (United States) Vol. 16; ISSN SCRMB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
BCC LATTICES
CRYSTAL DEFECTS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CUBIC LATTICES
DISLOCATIONS
ELEMENTS
INTERSTITIALS
LINE DEFECTS
MATHEMATICAL MODELS
METALS
POINT DEFECTS
RELAXATION
TRANSITION ELEMENTS