In-reactor defomation and fracture of austenitic stainless steels

Journal Article · Mon Jan 01 04:00:00 EST 1979 · Am. Soc. Test. Mater., Spec. Tech. Publ.; (United States)

OSTI ID:5348700

Bloom, E E ^[1]; Wolfer, W G

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1. Oak Ridge National Lab., TN

An experimental technique for determining in-reactor fracture strain was developed and demonstrated. Differential swelling between a specimen holder and a test specimen with a lower swelling rate produced uniaxial deformation in 304 and cold-worked 316 stainless steel specimens. In-reactor deformations of 0.7 to 2.1% were achieved in Type 304 stainless steel previously irradiated to fluences up to 8.8 x 10/sup 26/ neutrons (n)/m/sup 2/ without fracture. These strains are significantly higher than found in postirradiation creep-rupture tests on similar specimens. From the measured strain values and published irradiation creep data and correlations, the stress levels during the irradiation were calculated. On the basis of previous postirradiation creep-rupture results, many of the specimens that did not fail would be predicted to fail. Thus we conclude that the in-reactor rupture life is longer than predicted by post-irradiation tests. Strain in a fractured specimen was estimated to be less than 3.8%, and in the in-reactor fractures were intergranular - the same fracture mode as found in postirradiation tests. Irradiation creep may relax stresses at crack tips and sliding boundaries, thus retarding the initiation or growth of cracks, or both, and leading to longer rupture lives in-reactor. However, the very high ductility or superplastic behavior predicted by the strain-rate sensitivity or irradiation creep is not achieved because of the eventual interruption of the deformation process by grain boundary fracture.

• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 5348700
• Journal Information: Am. Soc. Test. Mater., Spec. Tech. Publ.; (United States), Journal Name: Am. Soc. Test. Mater., Spec. Tech. Publ.; (United States); ISSN ASTTA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360103* -- Metals & Alloys-- Mechanical Properties
360106 -- Metals & Alloys-- Radiation Effects
ALLOYS
CHROMIUM ALLOYS
CHROMIUM STEELS
CHROMIUM-NICKEL STEELS
CORROSION RESISTANT ALLOYS
CREEP
DEFORMATION
DUCTILITY
FAILURES
FRACTURES
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
IRON ALLOYS
IRON BASE ALLOYS
MATERIALS
MECHANICAL PROPERTIES
MOLYBDENUM ALLOYS
NICKEL ALLOYS
PHYSICAL RADIATION EFFECTS
RADIATION EFFECTS
STAINLESS STEEL-304
STAINLESS STEEL-316
STAINLESS STEELS
STEELS
STRAINS
SWELLING
TENSILE PROPERTIES