SYMPOSIA PAPER Published: 01 January 2000
STP12415S

Effects of Neutron Irradiation on Fe-Cu Model Alloys and RPV Steels Probed by Positron Annihilation and Hardness Measurements

Source

To study the formation of microvoids and Cu precipitates in Fe-Cu mode alloys (0–1.0 wt. % Cu) and A533B reactor pressure vessel (RPV) steel, positron lifetime and Vickers microhardness have been measured after fast neutron irradiation to a fluence of 8.3×1018n/cm2 below 150°C. Long positron lifetimes for the Fe-Cu alloys ranging from 300 to 420 ps and 270 to 350 ps for A533B RPV steels have been observed, which show microvoid formation. The long lifetimes in the Fe-Cu alloys depend on the Cu content and thermal aging at 550°C before irradiation. This fact suggests incorporation of irradiation-induced vacancies at Cu atoms and their precipitates leading to suppression of the microvoid formation. The long lifetime component for the Fe-Cu alloys recovers around 350°C, while that for A533B steel recovers around 300°C. To estimate the microvoid sizes, superimposed-atom model calculations of positron lifetimes in microvoids consisting of 1 (V1) to 66 (V66) vacancies have been performed, respectively. Based on these calculations, the formation and post-irradiation annealing behaviour of microvoids are examined.

In addition, irradiation-induced hardening monitored by Vickers microhardness is discussed with reference to positron annihilation experiments.

Author Information

Hempel, A
Institute for Materials Research, Tohoku University, Sendai, Japan
Saneyasu, M
Institute for Materials Research, Tohoku University, Sendai, Japan
Tang, Z
Institute for Materials Research, Tohoku University, Sendai, Japan
Hasegawa, M
Institute for Materials Research, Tohoku University, Sendai, Japan
Brauer, G
Institut für Ionenstrahlphysik und Materialforschung, Forschungszentrum Rossendorf e.V., Dresden, Germany
Plazaola, F
Elektrika eta Elektronika Saila, Euskal Herriko Unibertsitatea, Bilbo, Spain
Yamaguchi, S
Institute for Materials Research, Tohoku University, Sendai, Japan
Kano, F
Power and Instrumental Systems Research and Development Center, Toshiba Co., Kawasaki, Japan
Kawai, A
Power and Instrumental Systems Research and Development Center, Toshiba Co., Kawasaki, Japan
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: E10
Pages: 560–578
DOI: 10.1520/STP12415S
ISBN-EB: 978-0-8031-5419-3
ISBN-13: 978-0-8031-2852-1