摘要
The isothermal low cycle fatigue (LCF) and thermomechanical fatigue (TMF) behaviour of a Ni-base superalloy was investigated. The results show that temperature plays an important role in both LCF and TMF. The alloy shows the lowest LCF fatigue resistance in the intermediate temperature range (～760℃). For strain-controlled TMF, in-phase (IP) cycling is more damaging than out-phase (OP) cycling. The high tempera- ture exposure in the TMF cycling influences the deformation behaviour at the low temperature. LCF lives at different temperatures, and IP and OP TMF lives are successfully correlated by using the hysteresis parameter Δσ·Δε_p.
The isothermal low cycle fatigue (LCF) and thermomechanical fatigue (TMF) behaviour of a Ni-base superalloy was investigated. The results show that temperature plays an important role in both LCF and TMF. The alloy shows the lowest LCF fatigue resistance in the intermediate temperature range (～760℃). For strain-controlled TMF, in-phase (IP) cycling is more damaging than out-phase (OP) cycling. The high tempera- ture exposure in the TMF cycling influences the deformation behaviour at the low temperature. LCF lives at different temperatures, and IP and OP TMF lives are successfully correlated by using the hysteresis parameter Δσ·Δε_p.
