Effects of helium content on microstructural development in type 316 stainless steel under neutron irradiation

Thesis/Dissertation · Sun Jan 01 00:00:00 EST 1984

OSTI ID:5322253

Maziasz, P J

This work investigated the sensitivity of microstructural evolution, particularly precipitate development, to increased helium content during thermal aging and during neutron irradiation. Helium (110 at. ppm) was cold preinjected into solution annealed (SA) DO-heat type 316 stainless steel (316) via cyclotron irradiation. These specimens were then exposed side by side with uninjected samples. Continuous helium generation was increased considerably relative to EBR-II irradiation by irradiation in HFIR. Data were obtained from quantitative analytical electron microscopy (AEM) in thin foils and on extraction replicas. Normal aging produced small amounts of M/sub 23/C/sub 6/ (tau) precipitation at 560 to 600/sup 0/C, and tau plus large amounts of Laves phase at 650 to 700/sup 0/C. Preinjected helium eliminated tau and replaced it with Laves at 600 and 700/sup 0/C. Interstitial black-dot Frank loops were introduced via preinjection. These grew and coarsened upon long-term aging at 400 to 600/sup 0/C, and then unfaulted at 700/sup 0/C, apparently to provide vacancies for growing helium-vacancy clusters and bubbles.

• Research Organization: Tennessee Univ., Knoxville (USA)
• OSTI ID: 5322253
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
STAINLESS STEEL-316
PHYSICAL RADIATION EFFECTS
HELIUM
HIGH TEMPERATURE
MICROSTRUCTURE
QUANTITY RATIO
ALLOYS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
CORROSION RESISTANT ALLOYS
CRYSTAL STRUCTURE
ELEMENTS
FLUIDS
GASES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
MOLYBDENUM ALLOYS
NICKEL ALLOYS
NONMETALS
RADIATION EFFECTS
RARE GASES
STAINLESS STEELS
STEELS
360106* - Metals & Alloys- Radiation Effects