Prof. Bin Yang
30 Xueyuan Road, Haidian District
Beijing 100083, China
Tel. & Fax: +86-10-62333351
E-mail: byang@ustb.edu.cn
Dear Youshi Hong Editor,
We are pleased to submit the manuscript, “Fatigue property of SA508-ІV steel with different microstructures for a novel nuclear reactor pressure vessels” by Xin Dai, Yuefeng Chen and Bin Yang for your kind consideration and possible publication as an article inFatigue &Fracture of Engineering Materials & Structures .
The low cycle fatigue behavior of SA508-IV steel with different microstructures had been investigated. The fatigue test of the specimens with different microstructures were performed under the strain amplitudes of ±0.45% and ±0.6% at 300 °C, respectively. The experimental results showed that the fatigue life of martensite was much longer than that of granular bainite at the same strain amplitude, which might be attributed to four reasons: Firstly, the stress concentration between the M/A islands and bainitic ferrite matrix was easy to cause crack initiation. Secondly, the crack propagation of granular bainite was higher than that of martensite, which result in shorter fatigue life. Thirdly, the HAGBs volume fraction of martensite was much longer than that of granular bainite and the HAGBs could effectively hinder crack propagation. Finally, there were more carbides in martensite than in granular bainite and the carbides could effectively hinder crack propagation. Therefore, the fatigue life of martensite was much longer than that of granular bainite. And this paper provides reference data for the fatigue behavior of a novel reactor pressure vessel.
The work described in this paper is original. The manuscript, or its contents in some other form, has not been published previously by any of the authors and/or is under consideration for publication in another journal at the time of submission.
Thank you very much for your kind consideration.
Sincerely yours,