Creep behavior and mechanism of a notched γ′-rich Ni-based single crystal superalloy at high temperature

Release time:2026-02-05 Hits:

Journal:Materials Science and Engineering: A

Key Words:Advanced gas turbine single crystal blades withstand complex stress states during high temperature service. To elucidate the impact of these complex stress states on creep behavior of single crystal blades, this work designed V-notch specimens with a stress concentration factor of 3 and investigated their creep behavior at 1150 °C. At 1150 °C/100 MPa, the creep life of notched specimen is 4 times that of smooth specimen, demonstrating the strengthening effect of notch on the creep behavior of a Ni-based single crystal superalloy at an ultra-high temperature. Under stress concentration and a triaxial stress field, the notched specimen exhibits no change in crystal orientation during creep. The high dislocation density at the notch root indicates that with a little creep strain, the specimen produces coordinated deformation to release stress concentration. The great microstructural stability and dense interface dislocation networks are beneficial to reduce the impact of multi-axial stress components, which help improve the creep life of the notched specimens. The stress evolution results in the FEA are consistent with the experimental findings. This work contributes to understand the notch effect on the creep behavior of Ni-based superalloys, especially at ultra-high temperatures.

Indexed by:Journal paper

Correspondence Author:赵海根

Translation or Not:no

Date of Publication:2025-01-28

Included Journals:SCI