TY - JOUR
T1 - Calculation of alloying effect of Ruthenium in Ni-based single-crystal superalloys
AU - Sun, F.
AU - Zhang, J. X.
AU - Tian, Y.
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (Grant Nos. 50971078 and 51071096), Shandong Province Natural Science Foundation (Grant No. ZR2010EM009), and China Postdoctoral Science Foundation (special grade, Grant No. 201003630).
PY - 2012/7
Y1 - 2012/7
N2 - A first principles calculation method was used to investigate the site preference of platinum group metals (PGMs) at the γ/γ′ interface in Ni-based single-crystal superalloys. The calculation results show that the addition of PGMs can decrease the total energy and the binding energy of γ/γ′ interface, which may result in an improved microstructure stability of Ni-based single-crystal superalloys. Moreover, by calculation, it is also found that PGMs can stabilize both γ and γ′ phases and have a preference for Ni site at the coherent γ/γ′ interface. The influence of Ruthenium (Ru) on the partitioning behavior of W, Re, Cr and Mo in γ and γ′ phases was studied by Dmol3 calculation as well. It is found that when Ru substitutes the central Ni at the γ/γ′ interface, a reverse partitioning of W, Re and Cr occurs; while the partitioning behavior of Mo is not affected. Furthermore, electronic structure analysis of γ/γ′ interface in terms of Mulliken population and partial density of states (PDOS) was performed to understand the alloying mechanism of Ru in Ni-based single-crystal superalloys. The results show that the strengthening effect of Ru alloying is mainly due to the reduction in binding energy of Ru.
AB - A first principles calculation method was used to investigate the site preference of platinum group metals (PGMs) at the γ/γ′ interface in Ni-based single-crystal superalloys. The calculation results show that the addition of PGMs can decrease the total energy and the binding energy of γ/γ′ interface, which may result in an improved microstructure stability of Ni-based single-crystal superalloys. Moreover, by calculation, it is also found that PGMs can stabilize both γ and γ′ phases and have a preference for Ni site at the coherent γ/γ′ interface. The influence of Ruthenium (Ru) on the partitioning behavior of W, Re, Cr and Mo in γ and γ′ phases was studied by Dmol3 calculation as well. It is found that when Ru substitutes the central Ni at the γ/γ′ interface, a reverse partitioning of W, Re and Cr occurs; while the partitioning behavior of Mo is not affected. Furthermore, electronic structure analysis of γ/γ′ interface in terms of Mulliken population and partial density of states (PDOS) was performed to understand the alloying mechanism of Ru in Ni-based single-crystal superalloys. The results show that the strengthening effect of Ru alloying is mainly due to the reduction in binding energy of Ru.
KW - Alloying effect
KW - DMol3
KW - Electronic structure
KW - Ni-based single crystal superalloys
KW - Ruthenium
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U2 - 10.1016/j.commatsci.2012.03.049
DO - 10.1016/j.commatsci.2012.03.049
M3 - Article
AN - SCOPUS:84859709100
SN - 0927-0256
VL - 60
SP - 163
EP - 167
JO - Computational Materials Science
JF - Computational Materials Science
ER -