JAEA Fatigue Analysis of EBR-II Duplex Tubing.

Jackson, J. H. ; Porter, D. L. ; Lloyd, W. R.

Technical Information Center Oak Ridge Tennessee

关键词: Tubes;    Fatigue cracks;    Nickel bond layers;    Voids;    Oxide barriers;   

RP-ID  :  DE2009966150

学科分类：工程和技术（综合）

美国|英语

来源: National Technical Reports Library

【 摘 要 】

This work addresses questions brought up concerning the mechanisms associated with fatigue crack growth retardation and/or arrest within the nickel bond layer in duplex 2 and one fourth Cr-1Mo steel superheater tubes. Previous work performed at the Idaho National Laboratory (INL) indicated that the nickel bond layer did not function as a crack arrestor during fatigue crack propagation with the exception of one, isolated case involving an exceptionally low fatigue load and a high temperature (400 degrees C) environment. Since it is atypical for a fatigue crack to propagate from a relatively soft material (the nickel bond layer) to a harder material (the 2 and one fourth Cr-1Mo steel) there has been speculation that the nickel bond layer was hardened in service. Additionally, there are questions surrounding the nature of the fatigue crack propagation within the nickel bond layer; specifically with regard to the presence of voids seen on micrographs of the bond layer and oxidation within the steel along the edge of the nickel bond layer. There is uncertainty as to the effect of these voids and/or oxide barriers with respect to potential fatigue crack arrest.