Data details


Taxonomy tree DisplayHide Taxonomy tree
Number of page views : 11
TitleReport of Examination of the Samples from Core Shroud (2F3-H6a) at Fukushima Dai-ni Nuclear Power Station Unit-3 (Contract Research)
Alternative title福島第二原子力発電所3号機シュラウドサンプル(2F3-H6a)に関する調査報告書(受託研究)
AuthorThe Working Team for Examination Operation of Samples From Core Shroud at Fukushima Dai-ni Unit-3
Issued date2004-05
DescriptionThe present examination has been performed with the objective to ensure the transparency of the examination as the third-party organization by providing technical basis for identifying the causes of cracking through examination of the sample taken from the cracked region of outer H6a welding portion of the core shroud at Fukushima Dai-ni Nuclear Power Station Unit-3, which was a part of sample stored in the Nippon Nuclear Fuel Development Co., Ltd. in the examination of Tokyo Electric Power Company in 2001. The present examination of the sample was conducted at the post irradiation examination facilities of JAERI. The following findings were obtained from the result of the present examination. (1)Three cracks were observed at the portion 3 to 9mm apart from the weld metal and the maximum depth was about 8mm. (2)Intergranular cracking was observed in almost whole fracture surface. The transgranular cracking was partially observed within the depth of about 300mum from the surface. (3)Hardening layer over Hv400 at its maximum was found from the surface to the depth of about 500mum. Based on the examination results concerning presence of tensile residual stress by welding and relatively high dissolved oxygen contents in core coolant, it is concluded that the cracks were mainly initiated in the hardening layer by transgranular stress corrosion cracking and propagated along the grain boundaries.
Description著者所属: 日本原子力研究開発機構(JAEA)
Information sourceJOPSSRelation URLRelation URL
Related sites