Variation of the Corrosion Behavior Prior to Crack Initiation of E690 Steel Fatigued in Simulated Seawater with Various Cyclic Stress Levels

Journal Article · Sat Sep 15 04:00:00 EDT 2018 · Journal of Materials Engineering and Performance

DOI:https://doi.org/10.1007/S11665-018-3585-2· OSTI ID:22860258

Zhao, Tianliang; Liu, Zhiyong; Chao, Liu; Dai, Chunduo; Du, Cuiwei ^[1]; Li, Xiaogang ^[2]

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1. University of Science and Technology Beijing, Corrosion and Protection Center (China)
2. University of Science and Technology Beijing, Key Laboratory of Chinese Ministry of Education for Corrosion and Prevention (China)

The electrochemical process and corrosion behavior prior to crack initiation of E690 steel fatigued in simulated seawater are investigated under different cyclic stress levels by methods of electrochemical impedance spectroscopy, cyclic current response, electrochemical noise and morphology observation. The results show that the electrochemical behavior changes with the peak stress of cyclic loading and the corrosion behavior transforms as the peak stress increases over the proof strength. The charge transfer resistance (R{sub ct}) decreases with elevated peak stress. Continuous decreasing R{sub ct} with cycling number under peak stress of 1.02 σ{sub p0.2} indicates that continuous fresh metal induced by work-softening is exposed to the seawater, which is also proved by cyclic current response induced by cyclic stress and contact angle test. As a result, the corrosion type of E690 steel changes from general corrosion to pitting corrosion with the peak stress close to and above the proof strength. That induces the corrosion fatigue crack initiation mechanism to change correspondingly.

• OSTI ID: 22860258
• Journal Information: Journal of Materials Engineering and Performance, Journal Name: Journal of Materials Engineering and Performance Journal Issue: 9 Vol. 27; ISSN 1059-9495; ISSN JMEPEG
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BAINITE
COMPUTERIZED SIMULATION
CORROSION FATIGUE
CRACK PROPAGATION
ELECTROCHEMISTRY
IMPEDANCE
INCONEL 690
PITTING CORROSION
SEAWATER
SPECTROSCOPY
STRAIN SOFTENING
STRESSES
VARIATIONS