LCF behavior and lifing of a directionally solidified nickel base superalloy at high temperature
Isothermal low cycle fatigue (LCF) tests with and without hold time were performed at high temperatures in air on a directionally solidified nickel base superalloy. The influence of temperature and hold time on the cyclic stress response and fatigue life was studied. The results indicated that temperature had obvious affection on deformation of the alloy. At temperatures lower than 760℃,the alloy exhibited initial cyclic hardening,followed by a saturated cyclic stress response or cyclic softening under LCF. However,the alloy showed initial cyclic softening at 850℃ and 980℃,followed by a saturated cyclic stress response. There were different deformation mechanisms at different temperatures. The LCF lives were always short when strain dwell induced at peak strain,valley strain or peak and valley strain. The cyclic damage accumulation (CDA) method was used to predict the high temperature LCF life. The predicted life was found to be in good agreement with the experimental result.
Directionally solidified nickel base superalloy Creep-fatigue interaction Cyclic stress response LCF Life prediction Microstructure
H.C.Yu Y.Li X.R.Wu X.G.Yang D.Q.Shi
Beijing Institute of Aeronautical Materials,Beijing 100095,China Beijing University,of Aeronautics and Astronautics,Beijing 100083,China
国际会议
Fracture Mechanics and Applications 2008(国际断裂力学2008年年会)(FM2008)
杭州
英文
217-222
2008-10-31（万方平台首次上网日期，不代表论文的发表时间）