Computational Design of Cobalt-based Superalloy for Additive Manufacturing

Integrated Computational Materials Engineering (ICME) tools have been applied to the design of L1₂ precipitate-strengthened additive manufacturing Co-base superalloy. Thermodynamic database was optimized and used in the design to accurately predict microstructure features such as the γ/γ^’ phase fractions and compositions, and other precipitate formation. The microstructure features were used in material property models for printability optimizations, including γ^’ solvus, lattice misfit, hot crack resistance, oxidation resistance, and coarsening. Experimental prototype and characterizations were conducted as both validation and calibration for the ICME models, which shows good consistency with the CALPHAD modeling results. Multiple design cross-plots were generated to investigate the effects of varying elements on selected critical material properties. The optimized alloy composition serves as a promising candidate for printable Co superalloy.