High and low cycle fatigue characterization for 1.2709 maraging steel at different additively manufacturing conditions

The additive manufacturing (AM) is a relative new manufacturing process that belongs to the fourth industrial revolution, thus yielding new challenges that are worth the study in terms of reliability. In that sense, this work presents a comparative study of as printed and optimally heat-treated 1.2709 maraging steel manufactured by laser powder bead fusion (LPBF) AM process. The results suggest that parts were sound in terms of visual inspection and microstructural analysis. In the case of mechanical properties, the results suggest that the highest variability occurred after the heat treatment. The high cycle fatigue samples revealed a fracture without exhibiting a considerable amount of plastic deformation. On the other hand, the low cycle fatigue results revealed that at 1% strain the optimally heat-treated specimens have lower fatigue life due to the presence of surface discontinuities and the reduction of ductility after the heat treatment.