HVEM studies of helium embrittlement in stainless steel

Thesis/Dissertation · Tue Jan 01 00:00:00 EST 1980

OSTI ID:5386333

Horton, Jr, J A

In fast neutron irradiation environments, transmutation reactions occur in stainless steel which produce helium. The dissolved helium in the metal, along with the fast neutron-induced displacement damage leads to a premature integranular failure. A brittle intergranular fracture normally occurs in stainless steel at elevated temperature. The radiation environment apparently lowers the transition temperature between transgranular and intergranular failure. Helium embrittlement was studied by in situ tensile testing of three types of samples between 25/sup 0/C and 600/sup 0/C in an high voltage electron microscope with an attached accelerator. The three types of stainless steel samples used were: (1) previously fast-neutron irradiation, (2) 80 keV helium ion-irradiated during the tensile test inside the microscope and (3) unirradiated control samples. Post-failure analysis was then performed in an SEM in order to relate the transmission electron microscope observations to the overall type of fracture which was occurring. Many of the proposed theories explaining helium embrittlement rely on bubble enlargement in front of the crack tip until a certain area fraction covered by bubbles is achieved, at which point failure occurs.

• Research Organization: Virginia Univ., Charlottesville (USA)
• OSTI ID: 5386333
• Resource Relation: Other Information: Thesis (Ph. D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
STAINLESS STEELS
EMBRITTLEMENT
PHYSICAL RADIATION EFFECTS
FAST NEUTRONS
HIGH TEMPERATURE
MATERIALS TESTING
MEDIUM TEMPERATURE
TEMPERATURE EFFECTS
ALLOYS
BARYONS
CHROMIUM ALLOYS
CORROSION RESISTANT ALLOYS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
IRON ALLOYS
IRON BASE ALLOYS
NEUTRONS
NUCLEONS
RADIATION EFFECTS
STEELS
TESTING
360103* - Metals & Alloys- Mechanical Properties