Short crack initiation during low-cycle fatigue in UNS 32750 duplex stainless steel plate

MG MOSCATO; MC MARINELLI; S DEGALLAIX; I ALVAREZ

Grado and Aquileia

Congreso; 7th World Duplex 2007 Conference; 2007

AIM-Assoziazione Italiana de Metalurgia

In this work, the formation of fatigue cracks is considered as a nucleation process due to the development of a characteristic microstructure formed just beneath the specimen surface. Strain controlled cyclic tests were carried out at room temperature at total strain ranges of 0.8, 1.0 and 1.2% in flat specimens of rolling UNS S32750 Duplex Stainless Steel plates. The results show a strong influence of the dislocation structure formed just beneath the free surface on the formation of deformation induced martensitic transformation, microbands in grains and deformation bands crossing phases