티타늄 표면에서의 저출력 나노초 레이저의 조건별 초소수성 변화 경향성 연구

초록

This study investigates the effect of low-power (300 mW) nanosecond laser texturing on the formation of superhydrophobic structures on titanium surfaces. Five different laser conditions were applied, varying rep etition rate, scan speed, overlap rate, pulse width, and number of passes, while keeping the output constant. Sur face morphology and wettability changes were analyzed through scanning electron microscopy (SEM) and static contact angle measurements. Results showed that moderate passes (3–5 times) under high overlap conditions formed deep and continuous microgrooves, which favored the Cassie–Baxter state and resulted in increased con tact angles. However, excessive passes (≥10) led to thermal re-melting and flattening of surface features, thereby reducing contact angles or inducing irregular behavior. In some cases, high overlap rates caused flattening even with a low number of passes. The study highlights that optimal superhydrophobicity requires not only control of the number of passes but also a balanced combination of laser parameters to manage cumulative energy input. These findings demonstrate the feasibility of using low-power nanosecond lasers for functionalizing metallic sur faces and provide a guideline for process optimization in practical applications.

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