Fabrication of hierarchical structures on titanium alloy surfaces by nanosecond laser for wettability modification. (April 2022)

• Record Type: Journal Article
• Authors: Guo, Chunfang; Zhang, Meiju; Hu, Jun
• Is Part Of: Optics & laser technology. Volume 148(2022)
• Publication Date: 2022-04
• Subjects: Nanosecond laser -- Titanium alloy -- Hierarchical structures -- Contact angle -- Wettability; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2021.107728
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlights: Nanosecond laser was applied to fabricate hierarchical structures on titanium alloy with high efficiency. Surface morphology is determined by laser parameters and consequently modify the wettability of the surface. Laser processing is demonstrated as an effective approach for wettability control of titanium alloy surfaces. Abstract: Titanium alloy is widely used in aerospace industry due to its low density, high specific strength and high-temperature resistance. To broaden its application scope, superhydrophobicity of titanium alloy is required in certain situations, such as self-cleaning and anti-icing. In this study, direct nanosecond laser ablation was applied to fabricate distinct pits with hierarchical structures on titanium alloy substrates, followed with chemical treatment to modify the wettability of the surfaces. The effects of laser processing parameters on surface morphology and surface wettability were explored systematically. Results show that, increasing the number of scans improves the depth of the pits and the accumulation of the micro-nano structures around the craters. The scanning space mainly affects the overlap of the heat affected zones, and hence the distribution of the laser-induced hierarchical structures. The wettability of a laser processed surface is determined by both surface roughness and surface chemistry, and the solid fraction of the rough surface is regulated by the number of scans as well as the scanning space. Moreover, superhydrophobic surfaces are obtained on the laser processed titanium alloy after chemical treatment, which has great potential for the as-mentioned applications.