Laser assisted fabrication of superhydrophobic substrates for engineering applications

• Main Author: Zhang, Boyao
• Other Authors: Murukeshan Vadakke Matham
• Format: Thesis-Master by Coursework
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Engineering; Superhydrophobic substrates; Laser assisted fabrication; Anti-icing methods
• Online Access: https://hdl.handle.net/10356/181391
• Institution: Nanyang Technological University

Aircraft icing is one of the main hazards that affect the safe and efficient operation of aircraft. Icing on wings, engine intakes, and other critical components can lead to decreased aerodynamic performance, increased fuel consumption, and even flight accidents. Traditional deicing methods, such as thermal and chemical deicing, have problems like high cost and limited effectiveness. Therefore, it is important to find an efficient and environmentally friendly passive deicing method. In recent years, surface engineering methods based on ultrafast laser technology have shown great potential in the anti-icing field. Through ultrafast laser treatment, periodic superhydrophobic texture structures can be fabricated on the surface of the material. These structures can significantly reduce the ice adhesion force, delay the formation of ice, or even prevent the ice attachment completely. The super-hydrophobic surface uses its special micro-nano structure and low surface energy to form a gas-liquid interface, reducing the contact between water droplets and solid surfaces, thus greatly reducing the probability of ice formation. In this study, we investigated the enhancement of surface properties on an aluminum substrate through ultrafast laser processing, aiming to create superhydrophobic, textured surfaces with periodic structures for anti-icing applications. The laser-induced surface modification resulted in a significant increase in hydrophobicity compared to untreated aluminum, effectively minimizing ice formation by encouraging water droplets to slide off the surface rather than freeze. This superhydrophobic behavior played a critical role in disrupting ice nucleation, contributing to an efficient anti-icing mechanism. Ice adhesion tests showed a marked reduction in both the adhesion strength of ice to the laser-textured surfaces and the thickness of the ice layer. The force required to remove ice from the treated surfaces was considerably lower than for untreated aluminum, emphasizing the role of micro- and nanoscale structures in weakening the bond between ice and metal. These findings suggest that laser-structured surfaces may offer a superior, passive alternative to traditional deicing methods. Laser scanning confocal microscopy revealed the formation of uniform and compact periodic structures on the substrate, with high reproducibility and scalability, which are essential for maintaining stable anti-icing performance under varying conditions. Unlike traditional methods such as antifreeze sprays or thermoelectric deicing devices, the laser processing technique does not add significant weight or require additional energy input during flight, making it a more energy-efficient solution. This work paves the way for more effective and environmentally friendly ice management strategies in aerospace applications.