Grain boundary migration-induced directional coarsening of the γʹ phase in advanced ultra-supercritical superalloy
- Resource Type
- Authors
- Fei Ye; Jie Zhao; Tieshan Cao; Yan Wang; Congqian Cheng; Huifang Li; Fanghong Xu; Xiaohua Min; Qingshuang Xu
- Source
- Materials Science and Engineering: A. 714:172-178
- Subject
- 010302 applied physics
Dislocation creep
Materials science
Mechanical Engineering
02 engineering and technology
Slip (materials science)
021001 nanoscience & nanotechnology
Condensed Matter Physics
01 natural sciences
Supercritical fluid
Rod
Superalloy
Creep
Mechanics of Materials
0103 physical sciences
General Materials Science
Grain boundary
Composite material
0210 nano-technology
Microscale chemistry
- Language
- ISSN
- 0921-5093
This study investigated the features of grain boundary regions in a Ni-based superalloy which underwent creep deformation. Large grain boundary zones were denuded in fine γʹ precipitates but contained coarsened microscale γʹ rods. The coarsening direction of these rods was along the of the γ matrix and γʹ precipitates. The orientation of the grain boundary zone was the same as that of the adjacent grain behind the migrating boundary. This result indicated that the formation of these zones was accompanied by the migration of the grain boundary. Then, numerous slip features were observed through detailed local disorientation analysis. It is proposed that the driving force for the grain boundary migration was the local stress induced by the dislocation creep. The dissolution–reprecipitation of the precipitates at the boundary migration front resulted in the directional coarsening of the γʹ rods.