| Abstract Scope |
The combination of strength, corrosion resistance, and weldability makes IN625 attractive for additive manufacturing applications. A nitrogen content of approximately 0.1 percent promoted precipitation of unanticipated nitrides in both the as-deposited and post-process hot isostatically pressed (HIP) conditions. Cubic nitrides (MN), tetragonal Z-phase (CrNbN), and diamond-cubic η-nitrides (M6N) were found within the matrix containing relatively low Fe, Ti, and high Si contents, while a composition with higher Ti and Fe contents resulted in only MN nitrides. After HIP, many nitrides persisted in both materials with slight changes in secondary phase composition and lattice parameters. These stable nitrides present a potential pathway to enhanced high temperature and creep properties, but their impact on corrosion performance is currently unknown. A series of measurements evaluated the electrochemical performance of both alloys under free corrosion and potentiostatic conditions. The experimental protocol, and results from the electrochemical and microstructural analyses will be presented and discussed. |