Tensile properties of laser additive manufactured Inconel 718 using filler wire

This study investigates the tensile properties of laser additive manufactured Inconel 718 (IN718) using filler wire. The objective was to characterize the microstructure and evaluate the mechanical performance of direct laser deposited IN718 specimens on service-exposed IN718 parent metal substrates. Methodologically, a 5 kW continuous wave fiber laser welding system was employed to deposit the IN718 alloy, followed by room temperature tensile testing to assess yield and tensile strengths in comparison to aerospace specifications AMS 5596K and 5663M. The results indicated that while the yield and tensile strengths of the specimens were well above the minimum values stipulated in the specifications, the ductility at room temperature was found to be slightly lower. Furthermore, scanning electron microscopy (SEM) was used to analyze the tensile fracture surfaces of the service-exposed IN718 parent metal and the direct laser deposited specimens, revealing critical insights into the tensile failure mechanisms, specifically the roles of secondary particles and intermetallics. This research contributes to the understanding of the mechanical properties of laser additive manufactured superalloys, with implications for their application in aerospace components.