Abstract

The causes and mechanism of initiation and growth of pointed and linear pits, separations and cracks of corrosion origin on the internal surface of the shell of high-pressure ( 15.5 MPa ) steam boilers used at heat power plants were investigated by the LLMS, SEM, AES, SIMS and fractography methods. It was found as a result of comprehensive investigations that initiation and growth of the above damages were caused by hydrogenation and embrittlement of metal in the zones resulting from the simultaneous effect of an unfavourable local combination of several factors, such as formation of regions with a quenching structure and structural heterogeneity in the joining zone between dissimilar metals, many years of thermal cycling and corresponding thermal fatigue, local variations in chemical composition of metal in the intergranular and interface regions between the phases and corresponding variations in mechanical properties of given microvolumes of metal with a decreased crack resistance against the background of an increased sulphur content and decarburized surface layer of metal on the steam boiler drum shell.

Full Text
Paper version not known

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 call

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.