Corrosion Behavior of Additively Manufactured H13 Tool Steel in Salt Solution (3.5 wt% NaCl)

Abstract This study examines the corrosion resistance of H13 tool steel exposed to ionic molten salt solution through electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques. H13 steel samples were produced via selective laser melting (SLM) with three different build orientations (0 deg, 45 deg, and 90 deg) using the Build Processor v3.2 machine. Nyquist and Bode plots, along with polarization curves, were used to assess the impact of orientation on corrosion resistance. The findings were supported by microstructure analysis of the corroded samples using optical and scanning electron microscopies. The phase angle and the impedance modulus increased with building orientation, with the 0 deg orientation showing the highest values. Polarization resistance values were 1704 Ω cm2, 1540 Ω cm2, and 1430 Ω cm2 for 0 deg, 45 deg, and 90 deg, respectively, demonstrating superior corrosion resistance for the 0 deg orientation. Results highlight the critical impact of SLM build orientation on corrosion resistance, providing insights for future corrosion mitigation strategies for alloys.