Structural optimization and wetting behavior of femtosecond laser-fabricated micro-cone arrays on marine steel

Abstract To enhance marine equipment durability in harsh conditions, marine steel surfaces with high hydrophobicity are critical for anti-corrosion and self-cleaning, yet existing modification techniques lack stability, controllability, and consistency. Herein, 304 stainless steel substrates were processed via femtosecond laser to fabricate microcone arrays (spacings 150–350 μm, heights 150–350 μm), with systematic characterization of morphology, composition, crystal structure, and hydrophobicity. Results show regular micro-cones with smooth sidewalls (no slag), uniform element distribution, retained austenitic matrix, and minor edge oxidation, as confirmed by energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). Hydrophobicity varied with structure, peaking at 116.37° contact angle and 22° rolling angle, driven by synergistic air entrapment, laser-induced roughness, and oxide layer low surface energy. This work establishes a reliable process–structure–performance correlation, aiding the design of hydrophobic marine steels with strong engineering potential.