ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In this investigation, 3wt.% Ru was added to a low Cr and high W content superalloywith a nominal composition of Ni-10Co-1.5Cr-2.0Mo-1.0Nb-5.5Al-1.2Ti-0.1C-0.02B (wt.%) andboth the Ru-free and the Ru-bearing alloys were directionally solidified. The multi-step heattreatment, thermal exposure and stress rupture test were performed. The results indicate that Ru is aweak positive segregation element (k’=Cinterdendrite / Cdendrite= 1.03). The solubility of Ru in γ phaseis 30% higher than that of in γ' phase. Ru hardly enters into MC carbides, but can effectively retardthe formation of M6C carbides. Ruthenium reduces the amount of eutectic (γ+γ'), decreases solidsolution temperature of γ' phase, and promotes the rafting tendency of γ/γ' at elevated temperatures.Ru-bearing alloy possesses rather higher life at 1100°C/118MPa due to decrease of the film-likeM6C carbides. The addition of Ru can inhibit the formation of M6C and eutectic γ', which hinder theinitiation and propagation of cracks
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/55/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.353-358.507.pdf
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