Mechanical Performance and Material Characterization of Fused Filament Fabricated ABD 900 Superalloy

Abstract The material extrusion additive manufacturing (MEAM)/metal fused filament fabrication (MFFF) process for metal 3D printing is actively being sought as a potentially viable manufacturing option for jet engine propulsion materials. Its low cost, safety/ease in part manufacturing and operation coupled with its potential to efficiently develop deployable ready structures, makes it an attractive option for manufacturing of nickel-based superalloys, compared to laser powder bed fusion (LPBF) additive manufacturing technologies. ABD®900 is a nickel-based superalloy with high strength and corrosion/oxidation resistance at extreme temperatures, which has gained interest in its potential to be additively manufactured through the LPBF technology and reported to yield enhanced mechanical performance at high temperatures as compared with existing nickel-based superalloys, such as LPBF Inconel 718. This novel study is of the first of its kind to report on the ambient tensile response/properties and fracture mechanics exhibited by FFF ABD®900 green test coupons, and to assess the structural integrity of green and sintered cubes through material characterization techniques. Preliminary research findings on green tensile coupons and cubes reveal presence of considerable interlayer delamination and interlayer voids/porosity, with crazing marks evident on sample surface of green tensile coupons. A wide distribution of powder particles sizes is apparent, with most retaining their circular geometry but elliptical/oblong geometry of powder particles evident as well. Upon completion of the initial sintering cycle of cube specimens, presence of warping and shrinkage are quantifiably evident. The concluding position on the initial sintering trial identifies a need for precise furnace controls and understanding of part temperature as it transitions from green to brown to complete part densification.