| Numéro |
J. Phys. Colloques
Volume 48, Numéro C6, Novembre 1987
34th International Field Emission Symposium / 34ème Symposium International d'Emission de Champ
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| Page(s) | C6-429 - C6-434 | |
| DOI | https://doi.org/10.1051/jphyscol:1987670 | |
J. Phys. Colloques 48 (1987) C6-429-C6-434
DOI: 10.1051/jphyscol:1987670
CHARACTERIZATION OF IRRADIATED A533B PRESSURE VESSEL STEEL WELD
M.K. Miller1 et M.G. Burke21 Metals and Ceramics Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831-6376, U.S.A.
2 Department of Materials Science and Engineering, University of Pittsburgh, Pittsburgh, PA 15261, U.S.A.
Abstract
The microstructure of a neutron irradiated A533B pressure vessel steel weld has been characterized by atom probe field-ion microscopy. Many fine scale features including roughly spherical copper precipitates and clusters, spherical and rod-shaped molybdenum carbide and disc-shaped molybdenum nitride precipitates were observed inhomogeneously distributed in the ferrite matrix. The copper content of the ferrite was substantially reduced from the nominal level. A thin brightly-imaging film of molybdenum carbide and nitride was observed on grain boundaries. A large darkly-imaging copper-manganese precipitate was also observed on a boundary. Composition profiles indicated substantial enrichments of manganese and nickel at the precipitate-ferrite interface and that the enrichment extended into the ferrite. Enrichments of nickel, manganese and phosphorus were also measured at grain boundaries.