OS2114 Effect of long term thermal aging on crack propagation of a directionally solidified superalloy

Abstract

The effect of long term thermal aging (900℃, 30,000h) on fatigue crack growth behavior of a directionally solidified superalloy has been studied at both room temperature and high temperature (850℃). At room temperature, the threshold level of the stress intensity factor range, Δk_<th>, decreased for the aged specimen compared to the non-aged specimen. The results were discussed with relation to the microstructure.