Ferritic–Martensitic Structures and Their Effect on HAZ Notch Toughness

AbstractThe presence of a ferrite-martensite mixed microstructure in the HAZ ofa grade 65 line pipe steel, has been identified. The embrittling effect of this structure on the notch toughness of the HAZ is discussed. Resume La presence d'une microstructure composee d'un melange ferrite-martensite dans la zone affectee par la chaleur d'un acier it pipeline grade 65, a ete identifiee. L'effet de fragilisation de cette structure sur la sensibilite a l'entraille de la zone affectee est examine.