Improving the Processability of a One-Step Hydrophobic Coating for Hot-Dipped Galvanised Steel for Industrial Applications

Hydrophobicity on steel-based metallic surfaces provides an advantage in limiting corrosion and debris buildup on the surface, thereby, improving the substrate performance. An experimental investigation was conducted on the development of zinc stearate and silicon dioxide coatings on the surface of hot-dipped galvanised zinc-coated steel substrates, which could be used to induce superhydrophobicity. Under optimal formulation and processing conditions, a contact angle of 146 degrees could be produced within a 120-min processing window. This represents a reduction in processing time of 67% over previous literature using similar chemistry. In addition, we proved that costly nano silicon dioxide can be replaced by lower cost micro silicon dioxide without decreasing the performance of the coating contact angle. Under standard accelerated exposure tests, the coating was shown to reduce oxide build up by a factor of 3 compared to uncoated galvanized steel.

Automated summary

Hydrophobicity on steel-based metallic surfaces reduces corrosion and debris buildup, thus improving substrate performance. The study investigated the development of zinc stearate and silicon dioxide coatings on hot-dipped galvanised zinc-coated steel substrates, resulting in superhydrophobicity. Optimal processing conditions produced a contact angle of 146 degrees within a 120-min processing window, reducing processing time by 67% compared to previous literature. The study also proved that micro silicon dioxide can replace nano silicon dioxide without affecting the coating's contact angle performance. Additionally, the coating demonstrated a 3-fold reduction in oxide buildup compared to uncoated galvanized steel in accelerated exposure tests.