Abstract
An oxidation-resistant composite coating, including Mo-Si-B layer and Al2O3 diffusion barrier, was prepared on Nb-Si-based alloy by a two-step method. The Al2O3 film was fabricated by firstly deposition of Al on the alloy through pack cementation, and then by in situ oxidation of the aluminide coating. Mo-Si-B coating was then prepared on the Al2O3 film by spark plasma sintering. The Mo-Si-B coating is mainly composed of MoSi2 and a small amount of MoB and SiO2 particles. After long-term exposure at 1250 °C, the growth of the interdiffusion zone (IDZ) was suppressed effectively at the interface with the Al2O3 diffusion barrier. The results indicate that the diffusion barrier can significantly inhibit the outward diffusion of Nb, Ti and Cr alloying elements as well as the sluggish inward consumption of Si element. The Mo-Si-B coating with Al2O3 diffusion barrier exhibited a good oxidation resistance with a mass gain of about 0.97 mg/cm2 after 500 h of oxidation.
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.
