Abstract

Laves phase segregation is a universal phenomenon in additive manufactured or as-cast Inconel 718 alloy, and the Laves phase usually degrades the mechanical properties of the matrix. In this work, nickel-based alloys designed with different Nb contents were successfully fabricated by laser metal deposition (LMD) via a dual-feed system, and the Laves phase distribution at the macro level was relatively uniform. The effects of Nb content on the microstructure, mechanical properties and surface potential of the as-received and heat-treated nickel-based alloys were investigated. The grain size of the as-received LMD nickel-based alloys decreased with the Nb content, and the Laves phase exhibited a universally higher nano-hardness but lower surface potential than the γ matrix. The nano-hardness of the Laves phase linearly increased, whereas the Volta potential decreased with the Nb content. The strength improvement for the as-received LMD nickel-based alloys with different Nb contents was equally attributed to grain refinement and enhancement of the Laves phase (both hardness and content), while the increase in the precipitate content (main γ″) as a function of Nb content contributed to the substantial improvement in hardness for the heat-treated LMD nickel-based alloys and the grain refinement strengthening effect was comparative minor after aging treatment.

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.