Microstructural evolution in fast-neutron-irradiated austenitic stainless steels

Technical Report · Tue Dec 01 04:00:00 EST 1987

DOI:https://doi.org/10.2172/5436209· OSTI ID:5436209

Stoller, R E

The present work has focused on the specific problem of fast-neutron-induced radiation damage to austenitic stainless steels. These steels are used as structural materials in current fast fission reactors and are proposed for use in future fusion reactors. Two primary components of the radiation damage are atomic displacements (in units of displacements per atom, or dpa) and the generation of helium by nuclear transmutation reactions. The radiation environment can be characterized by the ratio of helium to displacement production, the so-called He/dpa ratio. Radiation damage is evidenced microscopically by a complex microstructural evolution and macroscopically by density changes and altered mechanical properties. The purpose of this work was to provide additional understanding about mechanisms that determine microstructural evolution in current fast reactor environments and to identify the sensitivity of this evolution to changes in the He/dpa ratio. This latter sensitivity is of interest because the He/dpa ratio in a fusion reactor first wall will be about 30 times that in fast reactor fuel cladding. The approach followed in the present work was to use a combination of theoretical and experimental analysis. The experimental component of the work primarily involved the examination by transmission electron microscopy of specimens of a model austenitic alloy that had been irradiated in the Oak Ridge Research Reactor. A major aspect of the theoretical work was the development of a comprehensive model of microstructural evolution. This included explicit models for the evolution of the major extended defects observed in neutron irradiated steels: cavities, Frank faulted loops and the dislocation network. 340 refs., 95 figs., 18 tabs.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 5436209
• Report Number(s): ORNL-6430; ON: DE88006045
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700209* -- Fusion Power Plant Technology-- Component Development & Materials Testing
ALLOYS
AUSTENITIC STEELS
COMPUTER CODES
CRYSTAL STRUCTURE
DAMAGING NEUTRON FLUENCE
DATA
DISPLACEMENT RATES
ELECTRON MICROSCOPY
ELEMENTS
EQUATIONS
EQUATIONS OF STATE
EXPERIMENTAL DATA
FLUCTUATIONS
FLUIDS
GASES
HELIUM
INFORMATION
IRON ALLOYS
IRON BASE ALLOYS
M CODES
MATERIALS
MICROSCOPY
MICROSTRUCTURE
NEUTRON FLUENCE
NEUTRON SPECTRA
NONMETALS
NUCLEATION
NUMERICAL DATA
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
RARE GASES
SPECTRA
STEELS
SWELLING
TEMPERATURE DEPENDENCE
THERMONUCLEAR REACTOR MATERIALS
TRANSMISSION ELECTRON MICROSCOPY
VARIATIONS
VOIDS