Multiaxial fatigue behavior of Ni-based superalloy GH4169 at 650 degrees C

作者：Shang De Guang^*; Sun Guo Qin; Chen Jian Hua; Cai Neng; Yan Chu Liang

来源：Materials Science and Engineering A-Structural Materials Properties Microstructure and Processing, 2006, 432(1-2): 231-238.

DOI：10.1016/j.msea.2006.06.014

• multiaxial fatigue
• cyclic hardening and-softening
• non-proportional loading
• high temperature
• Ni-based superalloy

The fatigue behavior of a Ni-based superalloy GH4169 was investigated using thin tubular specimens under multiaxial loading at 650 degrees C. Fatigue testing included multiaxial constant amplitude loading and variable amplitude block loading. The test results showed that the characteristics of cyclic hardening or softening depended on the strain loading paths, the sequence of the loading paths, and the loading parameters. Additional hardening due to non-proportional cyclic loading was still present at 650 degrees C, which caused the fatigue life to decrease. The sequence of the loading paths has an obvious influence on fatigue life, as shown by the increase in loading strain amplitude. Creep effect was observed in the multiaxial fatigue process at high temperature, and an increase in the number of cycles gradually strengthened the creep effect. Fractography showed intergranular fracture phenomena, which reflects the fatigue-creep, behavior under non-proportional cyclic loading at high temperature.

• 出版日期2006-9-25
• 单位北京工业大学