Vacancy migration enthalpy in tungsten at high temperatures

Conference · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7155994

Mundy, J N; Ockers, S T; Smedskjaer, L C

The curvature found in the Arrhenius plot for tungsten self-diffusion has been commonly interpreted in terms of simultaneous diffusion by two different defect processes. An alternative interpretation has been made in terms of the temperature dependence of the migration enthalpy and/or the formation enthalpy for single vacancies. In order to study the magnitude of the temperature dependence for the migration enthalpy, the present interrupted quenching experiments studied the annealing of a supersaturation of vacancies at high temperatures in tungsten. The temperature dependence of H/sup m//sub 1v/ found in the present experiments is insufficient to explain the Arrhenius curvature found for self-diffusion in tungsten. However, the curvature could be explained if the formation enthalpy, H/sup f//sub 1v/ had a temperature dependence of similar magnitude.

• Research Organization: Argonne National Lab., IL (USA)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 7155994
• Report Number(s): CONF-860953-10; ON: DE87004664
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DIFFUSION
ELEMENTS
METALS
MIGRATION
PHYSICAL PROPERTIES
POINT DEFECTS
QUENCHING
SELF-DIFFUSION
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENTS
TUNGSTEN
VACANCIES