Utilizing ICME Informed Inoculation to Solve Solidification Cracking and Improve Properties for Powder Bed Fusion Printed Alloy 230

Abstract Additive Manufacturing (AM) has revolutionized the production of complex geometries for demanding structural applications. Despite its transformative potential, many AM technologies encounter material challenges such as solidification cracking often observed in nickel-based superalloys. A notable example is Haynes 230 (H230), a solid-solution and carbide-strengthened nickel-based superalloy that is known for its excellent weldability with traditional arc based processes, but which suffers from extensive solidification cracking in laser powder bed fusion (PBF-LB). In this work, we developed an integrated computational materials engineering (ICME) framework to explain solidification cracking in this traditionally weldable alloy during processing with PBF-LB. We then leveraged this ICME approach and combined it with reactive additive manufacturing (RAM) technology to develop a new H230 variant, designated as Ni230-RAM1. This innovative alloy incorporates increased nucleation site density, promoting finer and more equiaxed grain formation during solidification. RAM technology effectively eliminates cracking, which significantly enhances mechanical properties. PBF-LB printed Ni230-RAM1 has greatly improved mechanical properties compared to printed, micro-crack containing unmodified H230, with a 38% increase in yield strength (YS), a 48% increase in ultimate tensile strength (UTS), and a 176% increase in elongation (EL%) at 760°C. Furthermore, the elevated temperature tensile and low cycle fatigue performance of PBF-LB Ni230-RAM1 is equivalent or superior to that of wrought Haynes 230. The generally superior mechanical performance of Ni230-RAM1 compared to both PBF-LB and wrought processed unmodified H230 is attributed to the crack free microstructure of PBF-LB Ni230-RAM1 combined with a finer grain size and a higher carbide volume fraction.