Abstract
AbstractDuring steam turbine rotor operation, the startup and showdown processes can cause asymmetric loading stress, leading to fatigue damage. To research the cyclic deformation behavior and fatigue failure mechanisms of 9% Cr‐based steel under asymmetric loading conditions, the strain ratios including −1, 0, and 0.1 are introduced into the low cyclic fatigue tests at 430°C. The results show the cyclic softening behavior is observed under three strain ratios at 430°C. As the strain ratio increases, the crack initiation sources, plastic strain, and consumed energy present an increasing trend. Comparing the microstructure morphology at different strain ratios, the coarsening lath and carbides affect fatigue crack initiation. Besides, the grain rotation and dynamic recrystallization can be observed, resulting in the cyclic softening behavior during the fatigue test. Finally, a new fatigue life prediction model is proposed at 430°C.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Fatigue & Fracture of Engineering Materials & Structures
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.