Study on Banded Structure in Low Carbon Vessel Plate for Nuclear Power Plant
In this paper, the role of the pearlite-banded structure on fatigue crack growth behavior was investigated on carbon vessel plate material SA516, which is commonly used in the nuclear power plants. Along pearlite-banded orientation, in situ fatigue tests indicate that the crack initiated and propagated in the ferrite and then extended along the ferrite-pearlite interface when it met pearlitic colony. For comparison, the cyclic loading was also carried out perpendicular to the banding direction of the microstructure, and an intense crack branching was observed which led to fatigue crack retardation. Besides, the orientation perpendicular to banded pearlite in the investigated ferrite-pearlite steel was found to have a lower fatigue crack growth rate.
F. Xue et al., "Study on Banded Structure in Low Carbon Vessel Plate for Nuclear Power Plant", Applied Mechanics and Materials, Vols. 44-47, pp. 1763-1766, 2011