抄録
In order to clarify the effect of the local stress distribution on the fatigue crack propagation rate of directionally solidified superalloy, elastic stress analysis was carried out with simulating grain configuration of a test specimen. Local stress along loading direction showed higher value near grain boundaries, which attained about 1.5 times as the average stress. The crack propagation rate obtained by the crack propagation test was accerelated at intermittent regions, which was coinside with the stress concentrating regions in the stress analysis. It was suggested that the local stress distribution may affect the crack propagation rate.
