Orientation-dependent Surface Topography, Microstructural Characteristics, and Corrosion Behavior of Additively Manufactured CuCrZr Alloy

This study investigates the influence of build orientation on the surface morphology, microstructure, and corrosion behavior of CuCrZr alloys fabricated by laser powder bed fusion (LPBF). The specimens were built at six angles of inclination (40°-90°) and were analyzed by scanning electron microscopy (SEM), 3D surface profilometry, and electrochemical techniques including electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, and potentiostatic testing in borate buffer solution. The findings indicate that building direction considerably influences surface roughness, subgrain structure, and porosity distribution, which impact passivation characteristics and charge transfer events. Samples fabricated at 50° exhibited minimum surface roughness and maximum grain homogeneity, leading to maximum polarization resistance and passive film stability. In contrast, samples fabricated at 90° exhibited maximum surface roughness, high current density, and low impedance values, reflecting poor passivation. Correlation of electrochemical performance with microstructure and topography identifies the paramount role of process-induced anisotropy in dictating corrosion resistance in LPBF-fabricated CuCrZr alloys.