Abstract
The Inconel 625 coatings with Nb addition of 0 %, 1.5 %, 3 % and 5 % were prepared by laser cladding technology. The effects of different contents of Nb on the phase composition, microstructure and corrosion resistance of the coatings were investigated by XRD, SEM, electrochemical test and other techniques. The results show that with the increase of the Nb content, the surface structure of the coating changes from dendrites to cellular crystals. Because of the consumption of C in γ-Ni phase by forming NbC, more Cr was released from its carbide state and solidly dissolved in γ-Ni phase, which improves its passivation capacity in the electrolyte. The increase of Nb also promotes more Nb and Mo elements to participate in the oxidation process. The plugging of pitting holes by corrosion products reduces the corrosion rate of coatings. The 3Nb coating exhibited the best corrosion resistance in 3.5%NaCl solution. The addition of an appropriate amount of Nb is an effective way to optimize the coating's microstructure, improve its corrosion resistance and microhardness.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
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.