A Coupled Modeling-Experimental Approach for Predictive Thermodynamic Modeling of Wire-Arc Directed Energy Deposition (DED) in Fe-10Ni and ER120S-1 Steels

Wire-arc directed energy deposition (DED) provides a more cost- and energy-efficient solution for the fabrication of large-scale parts compared to conventional manufacturing techniques, such as casting. However, materials fabricated via wire-arc DED can have different properties due to the cyclic heating that occurs during deposition. This study investigates the predicted volume fraction of phases, thermal history, microstructure, and mechanical properties of wire-arc DED-deposited ER120S-1 and Fe-10Ni feedstock wires and compares them to conventionally manufactured wrought high-yield (HY) steels. Thermodynamic and thermal macroscopic process finite element modeling was coupled with experimental characterization techniques including optical microscopy, scanning electron microscopy, tensile testing, and profilometry-based indentation plastometry (PIP). Finite element models for ER120S-1 and Fe-10Ni were calibrated using thermophysical properties generated from thermodynamic modeling and experimental measurements. The phase fractions were successfully predicted with ER120S-1 and Fe-10Ni deposits exhibiting similar or superior mechanical performance compared to wrought HY-80. The results validate the integrated computational materials engineering (ICME) process utilized and allow for further process optimization growth of wire-arc DED additive manufacturing (AM). This can help to tailor mechanical properties for desired performance metrics.