Neutron damage in reactor pressure-vessel steel examined with positron annihilation lifetime spectroscopy

Book · Sat Nov 01 04:00:00 EST 1997

OSTI ID:541148

Cumblidge, S E; Motta, A T; Catchen, G L ^[1]

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1. Pennsylvania State Univ., University Park, PA (United States). Nuclear Engineering Dept.

The authors have used positron annihilation lifetime spectroscopy to study the development of damage and annealing behavior of neutron-irradiated reactor pressure-vessel steels. They irradiated samples of ASTM A508 nuclear reactor pressure-vessel steel to fast neutron fluences of up to 10{sup 17} n/cm{sup 2}, and they examined these samples using positron annihilation lifetime spectroscopy (PALS) to study the effects of neutron damage in the steels on positron lifetimes. Non-irradiated samples show two positron lifetimes: a 110 ps component corresponding to annihilations in the bulk material, and a 165 ps lifetime corresponding to annihilations in dislocation defects. The irradiated samples show an additional lifetime component of 300 ps in the PAl spectra and an increase in the proportion of annihilations with a 165 ps lifetime, suggesting that vacancies and vacancy clusters are present in the material after room temperature irradiation. The samples were then annealed to temperatures ranging from 210 C to 450 C. The positron lifetimes introduced by neutron damage disappear after annealing the samples at 280 C.

• OSTI ID: 541148
• Report Number(s): CONF-961202--; ISBN 1-55899-343-6
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
36 MATERIALS SCIENCE
CRYSTAL DEFECTS
EMBRITTLEMENT
EXPERIMENTAL DATA
PHYSICAL RADIATION EFFECTS
POSITRONS
PRESSURE VESSELS
REACTOR MATERIALS
STEEL-ASTM-A508