Abstract
ABSTRACT The creep rupture ductility of not only creep strength enhanced ferritic steels but also conventional 2.25Cr-1Mo steels was investigated, focusing on the remarkable decrease in ductility in the long term. The decrease was well described as a function of yield ratio of applied stress and appeared at about 50% of the 0.2% offset yield stress at the creep test temperature with decrease in the yield ratio. A trade-off relation between creep rupture strength and creep rupture ductility was found for Grade T/P23 steels. The similar trade-off relation between creep strength and ductility was observed also for conventional 2.25Cr-1Mo steels. A remarkable drop in creep rupture ductility of quenched and tempered 2.25Cr-1Mo steels was found in conjunction with a large drop in creep rupture strength. This remarkable drop was considered to be caused by microstructural changes due to the inhomogeneous progress of recovery of tempered martensitic microstructure. A modified heat treatment process with intermediate tempering on partially quenched dual phase microstructure was found to have a beneficial effect on creep rupture ductility for Grade P92 steel. This was considered to be the result of the reduction in residual stress introduced by martensitic phase transformation accompanied with shape change and volume expansion.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
