Method and Mechanism Study on Inhibiting High-Temperature Corrosion of Aluminum Alloys by Gallium-Based Liquid Metal Alloys With Columnar Arrays

Abstract

Gallium-based Liquid Metal Alloys (GLMA), known for their superior heat transfer capabilities and eco-friendly nature, unfortunately, pose a significant corrosion threat to metals like aluminum alloys, especially at elevated temperatures. This study explores the dynamic and static wetting behaviors of GLMA across various settings and its corrosive interactions with aluminum alloys at high temperatures. We introduce a novel approach that employs a laser-crafted aluminum alloy columnar array to curtail the high-temperature corrosion inflicted by GLMA. Our experiments reveal  GLMA's high surface tension minimally affects the static wetting on aluminum alloy samples. Intriguingly, when GLMA droplets are compressed against the columnar array surface of the aluminum alloy, they tend to spread horizontally before seeping vertically under external pressure. This columnar structure significantly hinders direct contact between GLMA and the base material, thus reducing the contact area and mitigating corrosion. On standard aluminum alloy surfaces, the corrosion rate escalates with temperature, enlarging the affected area. Contrastingly, the aluminum alloy columnar array surface markedly obstructs GLMA's high-temperature corrosion. Even under extreme conditions, such as temperatures up to 500°C and exposure for 10 hours, GLMA droplets remain intact without showing signs of rupture, collapse, or diffusion on the substrate. The research results pave the way for a new strategy for mitigating the high-temperature corrosion of metal materials caused by GLMA in heat transfer applications.

Keywords: Liquid metal, High-temperature corrosion, Laser processing, Columnar array structure, Wetting.