TY - JOUR
T1 - Investigation on influence of Ta on microstructure evolution of directionally solidified Ni-based superalloys
AU - Peng, Peng
AU - Lu, Li
AU - Liu, Zijie
AU - Xu, Yuanli
AU - Zhang, Xudong
AU - Ma, Zhikun
AU - Zhang, Hong
AU - Guo, Min
AU - Liu, Lin
N1 - Publisher Copyright:
© 2022 Elsevier B.V.
PY - 2022/12/15
Y1 - 2022/12/15
N2 - The microstructure evolution in directionally solidified Ni-based superalloys DZ411 with different Tantalum (Ta) compositions (2.72, 3.10, and 4.00 wt%) was investigated to develop Ta-containing hot corrosion superalloys. It is found that the addition of Ta promote the element segregation in the interdendritic region, thus, leading to the increase in volume fraction of MC carbides and eutectics, while the morphology of them are not obviously changed. In addition, both the volume fraction of regions increases with increasing Ta composition, which is attributed to the reason that Ta is the main forming element of γ' phase. Besides, the previous controversy on the dependence of both the primary and secondary dendrite arm spacing on Ta composition was solved. The increase of dendrite arm spacing with increasing Ta composition can be attributed to increasing solidification range of these superalloys through both JMatPro and Different Scanning Calorimetry (DSC) analysis. Furthermore, the atomic arrangement of γ and γ' phases in alloys was characterized by spherical aberration corrected transmission electron microscopy. Both the saturation of refractory elements in γ matrix and the lattice constant of γ matrix was found to increase with increasing Ta composition, leading to the increase of lattice mismatch of γ/γ' phase and more regular shape of γ' phase which has also been confirmed by JMatPro analysis.
AB - The microstructure evolution in directionally solidified Ni-based superalloys DZ411 with different Tantalum (Ta) compositions (2.72, 3.10, and 4.00 wt%) was investigated to develop Ta-containing hot corrosion superalloys. It is found that the addition of Ta promote the element segregation in the interdendritic region, thus, leading to the increase in volume fraction of MC carbides and eutectics, while the morphology of them are not obviously changed. In addition, both the volume fraction of regions increases with increasing Ta composition, which is attributed to the reason that Ta is the main forming element of γ' phase. Besides, the previous controversy on the dependence of both the primary and secondary dendrite arm spacing on Ta composition was solved. The increase of dendrite arm spacing with increasing Ta composition can be attributed to increasing solidification range of these superalloys through both JMatPro and Different Scanning Calorimetry (DSC) analysis. Furthermore, the atomic arrangement of γ and γ' phases in alloys was characterized by spherical aberration corrected transmission electron microscopy. Both the saturation of refractory elements in γ matrix and the lattice constant of γ matrix was found to increase with increasing Ta composition, leading to the increase of lattice mismatch of γ/γ' phase and more regular shape of γ' phase which has also been confirmed by JMatPro analysis.
KW - Directional solidification
KW - Lattice mismatch
KW - Ni-based superalloys
KW - Tantalum
UR - http://www.scopus.com/inward/record.url?scp=85137276137&partnerID=8YFLogxK
U2 - 10.1016/j.jallcom.2022.167009
DO - 10.1016/j.jallcom.2022.167009
M3 - 文章
AN - SCOPUS:85137276137
SN - 0925-8388
VL - 927
JO - Journal of Alloys and Compounds
JF - Journal of Alloys and Compounds
M1 - 167009
ER -