Subtask 12F2: Microstructural evolution of V-4Cr-4Ti during neutron irradiation

Technical Report · Wed Mar 01 04:00:00 EST 1995

DOI:https://doi.org/10.2172/415186· OSTI ID:415186

Chung, H. M.; Gazda, J.; Loomis, B. A. ^[1]

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1. Argonne National Lab., IL (United States)

The objective of this work is to characterize the microstructural evolution of V-4Cr-4Ti alloy during irradiation by fast neutrons, and thereby to provide a better understanding of long-term performance of the alloy under fusion conditions. Microstructural evolution of V-4Cr-4Ti, an alloy recently shown to exhibit excellent tensile and creep properties, virtual immunity to irradiation embrittlement, and good resistance to swelling, was characterized after irradiation in a lithium environment in the Fast Flux Test Facility (FFTF) (a sodium-cooled fast reactor located in Richland, Washington) at 420, 520, and 600{degrees}C to 24-34 dpa. The primary feature of microstructural evolution during irradiation at 520 and 600{degrees}C was high-density formation of ultrafine Ti{sub 5}Si{sub 3} precipitates and short dislocations. For irradiation at 420{degrees}C, precipitation of Ti{sub 5}Si{sub 3} was negligible, and {open_quotes}black-dot{close_quotes} defects and dislocations were observed in significantly higher densities. In spite of their extremely high densities, neither the {open_quotes}black-dot{close_quotes} defects nor Ti{sub 5}Si{sub 3} precipitates are overly detrimental to ductility and toughness of the alloy, yet they very effectively suppress irradiation-induced swelling. Therefore, these features, normally observed in V-base alloys containing Ti and Si, are considered stable. Unstable microstructural modifications that are likely to degrade mechanical properties significantly were not observed, e.g., irradiation-induced formation of fine oxides, carbides, nitrides, or Cr-rich clusters. 18 refs., 4 figs., 1 tab.

• Research Organization: Argonne National Lab., IL (United States)
• OSTI ID: 415186
• Report Number(s): ANL/FPP/TM--287; ITER/US--95/IV-MAT-10; ON: DE96000984
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
CHROMIUM ALLOYS
IRRADIATION
ITER TOKAMAK
MICROSTRUCTURE
PHYSICAL RADIATION EFFECTS
TITANIUM ALLOYS
VANADIUM BASE ALLOYS