Abstract
In this study, creep rupture behaviors and rupture mechanism of dissimilar metal weld (DMW) between Inconel 617B and modified 9%Cr martensitic heat-resistant steel (hereinafter referred to 9Cr steel) with Inconel 617 filler metal were investigated. Creep tests were carried out at 600 °C and 620 °C in the stress range 130–240 MPa. Optical microscopy (OM), scanning electron microscopy (SEM), Electro-Probe Microanalyzer (EPMA) and micro-hardness test were used to examine the creep rupture behaviors and microstructure characteristics of the DMW. The results indicated that under different creep conditions, the rupture locations varied, including 9Cr base metal (BM), the intercritical heat affected zone (ICHAZ) of 9Cr steel, and the interface between weld metal (WM) and 9Cr steel. The rupture behavior occurring in the 9Cr BM was mainly controlled by plastic deformation, and the growth and coalescence of dimples eventually led to transgranular fracture. The rupture behavior occurring in the ICHAZ was caused by type IV crack due to matrix softening and lack of sufficient precipitates pinning the grain boundaries (GBs). The rupture behavior occurring at the interface was mainly related to the oxide notch forming at the interface. The formation and propagation of the oxide notch resulted in the interfacial failure.
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.
