Abstract
This paper examines a life prediction method for a low strengh and high ductility material, cast Co base superalloy (10Ni-29Cr-7W-0.2Ti-0.25Nb-0.15Zr-0.40C-Co), under fatigue-creep interaction (FCI) conditions.
We previously proposed a frequency modified total strain energy parameter to evaluate failure lives (Nf), crack initiation lives (Nc) and surface crack propagation behavior for high strength superalloy under FCI conditions. The frequency modified total strain energy parameter was obtained from the total tensile strain energy (ΔWTT) and loading time (τTT) under tensile stress.
This paper examines the suitability of applying the frequency modified total strain energy to life prediction and crack propagation behavior evaluation for cast Co base superalloy. We have found that not only crack initiation and failure lives, but also crack propagation behavior of cast Co base superalloy under FCI conditions can be estimated exactly by using the frequency modified total strain energy parameter.
