Durable slippery liquid-infused porous surfaces for effective corrosion protection of aluminum alloy in ethylene glycol-water solutions

Abstract

Aluminum (Al) alloys are extensively utilized in liquid-cooling heat dissipation systems owing to their superior strength-to-weight performance, ease of processing, and high thermal conductivity. However, they are susceptible to corrosion in the cooling medium, such as ethylene glycol-water solutions. This study presents a straightforward and cost-effective method to create a slippery liquid-infused porous surface (SLIPS) designed to effectively prevent corrosion of the 6061 Al alloy in ethylene glycol-water solutions. Micro/nano hierarchical structures were achieved on the SLIPS through plasma electrolytic oxidation and hydrothermal treatment. Following the modification of low-surface-energy materials and the infusion of silicone oil, the SLIPS exhibited an outstanding slippery property, allowing ethylene glycol-water droplets to effortlessly slide down the inclined surface at an angle of 1.1°. Additionally, the SLIPS demonstrated remarkable anti-corrosion performance against ethylene glycol-water solutions, with a minimum corrosion current density (Icorr) of 2.4 × 10−10 A·cm−2. Crucially, long-term immersion test results on corrosion resistance revealed that the SLIPS provided reliable corrosion protection for the 6061 Al alloy, exhibiting an Icorr increased by 4 orders of magnitude compared to a smooth substrate. These findings hold significant potential for advancing the widespread application of SLIPS in liquid-cooling heat dissipation systems.