%A Huanchun WU, Fei XUE, Chengtao LI, Kewei FANG, Bin YANG, Xiping SONG %T Fatigue Crack Initiation Behaviors of Nuclear Power Plant Main Pipe Stainless Steel in Water with High Temperature and High Pressure %0 Journal Article %D 2018 %J Materials Reports %R 10.11896/j.issn.1005-023X.2018.03.005 %P 373-377 %V 32 %N 3 %U {http://www.mater-rep.com/CN/abstract/article_8.shtml} %8 2018-02-10 %X

The behaviors of fatigue crack initiation of 316LN and Z3CN20.09M austenite stainless steels (ASSs) were studied by corrosion fatigue test system in high temperature water. The results indicated that the fatigue cracks were mainly initiated at the persistent slip bands (PSBs) on the surface of 316LN ASS. Only a few cracks were initiated at the sub-grain boundaries. While the fatigue cracks were sequentially initiated at PSBs, phase boundaries and corrosion pits of the Z3CN20.09M ASS containing a little part of ferrite, and they were also mainly initiated at PSBs. The crack initiation mechanism at PSBs was analyzed based on composition of oxide film and morphology of cross section of the specimens tested in high temperature water. Moreover, the difference of the crack initiation mechanisms for two kinds of stainless steel was analyzed. Finally, the effect of the ferrite phase on corrosion fatigue property was summarized.