Investigating the long-term anti-corrosion property of epoxy coatings via hydrothermal ageing (PRES2026-00039)

Mark Pasciolco, John Loui Tadia, Chrissen Juvileen dela Cruz Galang, Qiong Wu, Wei Han, King Lun Yeung

The Hong Kong University of Science and Technology, The Hong Kong University of Science and Technology, The Hong Kong University of Science and Technology, The Hong Kong University of Science and Technology,

Corrosion is the primary reason for defects and failures in the freshwater and seawater pipelines of Hong Kong. Using internal lining in pipes continues to be one of the most economical methods to prevent this issue. This study aims to determine the long-term performance of different epoxy coatings by accelerated ageing. Among the commonly used method to immediately deteriorate a material is via hydrothermal ageing. Four (4) different industrial coatings were used in this study. Samples were immersed in both freshwater and seawater and placed in elevated temperature. An ageing ratio was established in accordance with ASTM F1980-21. Anti-corrosion performance of the coatings was assessed by Tafel test after 4, 8, and 16 weeks of hydrothermal ageing. It was found that ceramic epoxy coatings still had above 90% of corrosion inhibition efficiency (CIE) even on the 16th week of hydrothermal ageing, while the coating with no nanofiller experienced a significant decrease in its anti-corrosion performance. Therefore, ceramic epoxy coatings can still protect the seawater and freshwater pipes in the water distribution networks of Hong Kong for atleast two (2) years.