Influence of Ru and Cr on the Heat-Treated Microstructure of Ni-Based Superalloys


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The effects of ruthenium and chromium contents have been investigated on phase transformation temperatures and the morphology of γ’ precipitates as well as microstructural stability in high refractory Ni-base superalloys. The solidus and liquidus temperatures were determined by differential scanning calorimetry (DSC), suggesting that the addition of Cr resulted in a decrease in solidus/liquidus temperatures while the Ru addition (3.5 at.%) had the neutral effect. The morphology of γ’ precipitates in the heat-treated microstructure was changed under the influence of the Cr and Ru additions, suggesting that Ru and Cr contents affected the γ−γ’ lattice misfit through changes in the associated partitioning to the constituent phases. The microstructural instability has been investigated at 1000 oC. High levels of Cr addition (8 at.%) strongly promoted the formation of TCP phases, while Ru improved the microstructural stability to some extent.



Materials Science Forum (Volumes 546-549)

Edited by:

Yafang Han et al.




W.B. Wang et al., "Influence of Ru and Cr on the Heat-Treated Microstructure of Ni-Based Superalloys", Materials Science Forum, Vols. 546-549, pp. 1207-1210, 2007

Online since:

May 2007




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