[2H01-04] Reactor Pressure Vessel

[2H01] FY2018 Investigation for Improvement of Evaluation Method of Irradiation Effects on Reactor Pressure Vessel and Core Internals

(1)Through-wall fracture toughness distribution of decommissioned Zion Unit 1 reactor pressure vessel steel

*Masato Yamamoto¹, Tomohiro Kobayashi¹ (1. CRIEPI)

Keywords:Reactor Pressure Vessel Steel, Zion Unit 1 Nuclear Power Plant, Decomissioned Reactor Pressure Vessel Material, Fracture Toughness, Master Curve Method

Through-wall fracture toughness distribution was studied using beltline base metal steel of decomissioned Zion Unit 1 RPV material. Near surface region possesed higher fracture toughness than that in 1/4-thick location, which is specified as specimen retrieval position of surveillance tests, for both of T-L and L-S orientations. Fracture toughness graduary increased with increasing distance from reactor core, indicating the effect of neutron attenuation on irradiation shift of fracture toughenss through the RPV wall direction.