Investigation of Capillary Rise on the Aluminum Substrates Structured by Nanosecond Laser Irradiation

Nanosecond laser structuring of aluminum alloy was investigated to optimize microchannel geometry for enhanced capillary rise. Microchannels with varying density of scan lines were fabricated and characterized. Medium densities yielded the highest deionized water rise velocity and stable transport, following the Lucas–Washburn law. The efficiency was attributed to hierarchical micro/nanostructures and the aluminum oxide layer formed during processing, enhancing hydrophilicity. High densities caused channel merging, reducing flow directionality. Results demonstrate the potential of nanosecond lasers for producing cost-effective, high-performance supercapillary surfaces.