Influence of thermomechanical postprocessing on creep behavior of Inconel 718 superalloy prepared by additive manufacturing

Additive manufacturing represents a promising alternative to the conventional technologies used for the production of metallic materials. However, in contrast to the conventional approaches, materials produced using additive manufacturing typically feature certain disadvantages. One possibility to reduce their negative effects is to subject the additively manufactured materials to post processing via intensive plastic deformation. The present work primarily studies the creep behavior of Inconel 718, a nickel-based superalloy with a wide applicability in challenging industries, at four different initial material states (additive and conventional manufacturing, and subsequent post-processing via rotary swaging). A rather unique plastometric experimental methodology of accelerated creep testing, which consists of a slow plastic deformation of a material under long-term stress at an elevated temperature, was then used to study the behavior of the prepared samples.