About this Abstract |
Meeting |
Superalloys 2024
|
Symposium
|
Superalloys 2024
|
Presentation Title |
C-1: Effect of Re Addition on the Sensitivity to Recrystallization in As-cast Ni-based SX Superalloys |
Author(s) |
Yihang Li, Zhipeng Jiang, Longfei Li, Guang Xie, Jian Zhang, Qiang Charles Feng |
On-Site Speaker (Planned) |
Yihang Li |
Abstract Scope |
The recrystallization of nickel-based single-crystal superalloys during solution treatment may be promoted by local deformation induced during the cooling stage of directional solidification and is related to alloy chemistry. In this study, the effect of Re addition on the sensitivity to recrystallization of nickel-based single-crystal superalloys and the ways in which Re affects nucleation and growth of recrystallized grains are investigated using the as-cast alloy without Re addition and those with Re addition of 2 and 4 wt.%. It is suggested that 4 wt.% Re addition can significantly increase the propensity to nucleate recrystallized grains but significantly inhibit grain growth of the as-cast SX superalloy. The former is attributed to the increase of Re segregation at the dendrite scale, which leads to the increase of strength difference in ã matrix of the dendrite core and interdendritic region, as well as the increase in eutectics and casting pores, thus providing higher stored energy and more nucleation sites for recrystallization nucleation. Meanwhile, the severe Re segregation in ã matrix of high-Re alloys increases the ã′ solvus temperature and reduces the precipitate-free zone, thus inhibits growth of recrystallized grains. These insights will be beneficial to alloy design and process optimization and allow further improvement of the casting costs. |
Proceedings Inclusion? |
Definite: At-meeting proceedings |