Fatigue behaviour of an additively manufactured ductile gas turbine superalloy

•The LCF life at room temperature of an AM nickel-based superalloy was studied.•A constitutive model and a crack initiation model was developed.•The models predicts the experimental response with good agreement.•The fracture surfaces were studied using ECCI and EBSD.•The dendritic structure had some effects on the LCF crack propagation behaviour.