Abstract

The oxidation behavior of a Co32Ni21Cr8Al0.6Y (wt%) alloy with and without the addition of 3.5 wt% rhenium, 2 wt% aluminum or a combination of the two was investigated at 1000 °C. Results showed that increasing the Al content from 8 to 10 wt% led to an increase of the alloy β-phase, but did not affect the oxidation behavior. Re addition induced (Cr,Re,Y)-rich phase to precipitate in the alloy, accelerated the θ- to α-alumina transformation, reduced the oxidation rate and enhanced the rate of alloy Al diffusion. Adding both Al and Re further improved the oxidation behavior by promoting the development of the external alumina scale and suppressing the formation of Ni, Co containing spinel. This alloy also showed the largest reduction of oxidation rate and emerged to be the most beneficial. A continuous Cr–Re rich layer was observed at the oxide/alloy interface of the Re, Al containing alloy after longer oxidation times, but this layer is not expected to affect the continued growth of the alumina scale.

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.