Study of the mechanism of fast diffusion of cobalt in thorium by diffusion and internal friction measurements

Journal Article · Tue Oct 31 23:00:00 EST 1989 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (USA)

DOI:https://doi.org/10.1007/BF02666664· OSTI ID:6986554

Axtell, S C ^[1]; Carlson, O N ^[2]

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1. Metallurgy Engineering Dept., South Dakota School of Mines, Rapid City, SD (US)
2. Ames Lab., Iowa State Univ., Ames, IA (US)

The activation energy for diffusion, {ital Q{sub D}}, of cobalt in fcc thorium was determined to be 83.7 {+-} 4 kJ/mol from chemical diffusion measurements between 900{degrees}C and 1332{degrees}C. An internal friction peak associated with cobalt was identified at 45{degrees}C, and the activation energy for relaxation, {ital Q{sub R}}, was found to be 76.0 {+-} 1.5 kJ/mol by a frequency variation technique. The nearly equal values for {ital Q{sub D}} and {ital Q{sub R}} eliminate the interstitial-vacancy pair mechanism for fast diffusion in this system. The host-solute diplon and substitutional-interstitial (S-I) pair models for fast diffusion are considered and preference is given to the latter mechanism for cobalt in thorium.

• OSTI ID: 6986554
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (USA), Journal Name: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (USA) Vol. 20A:11; ISSN MTTAB; ISSN 0360-2133
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
640302 -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
ACTINIDES
ACTIVATION ENERGY
ATOM TRANSPORT
COBALT
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DIFFUSION
ELEMENTS
ENERGY
INTERACTIONS
INTERNAL PAIR PRODUCTION
METALS
NEUTRAL-PARTICLE TRANSPORT
PAIR PRODUCTION
POINT DEFECTS
RADIATION TRANSPORT
THORIUM
TRANSITION ELEMENTS
VACANCIES