A new perspective on the mechanical behavior of Inconel 617 at elevated temperatures for small modular reactors
Benhour Amirian, Asad Asad, Logan Krezan, Mostafa Yakout, James D. Hogan
Abstract
This study investigates the temperature-dependent mechanical properties of Inconel 617, a nickel-based superalloy, for small modular reactor applications. The formation of the sigma phase, driven by high chromium content during prolonged high-temperature exposure, significantly impacts the alloy's strength, creep resistance, stress rupture life, and ductility. The transition temperature for sigma phase formation is predicted to be approximately 1064 C ∘ , with an uncertainty range between 700 C ∘ and 1250 C ∘ , confirmed through an uncertainty analysis of elemental composition. Chromium is identified as the primary element influencing sigma phase stability. Additionally, hot tearing susceptibility during solidification is assessed, revealing that a carbon content of 0.08 wt % minimizes the cracking susceptibility coefficient to 0.425, reducing the risk of solidification cracking. These findings offer critical insights for optimizing the composition and processing conditions of Inconel 617 in laser-directed energy deposition additive manufacturing.