Corrosion and Wear Resistance Aptitude Tests of SERMETEL Coatings under Aggressive Environments

The Q235 steel is known for its good toughness and castability, making it easy to stamp and weld as a substrate. For the coating, SERMETEL water-based high-temperature coatings are used. One part of the first coating primer is applied using a closed coatings shot blasting method after surface cleaning 17-4PH stainless steel surfaces, while the other part is dry coated with closed coatings after the sandblasting process. The coatings were tested for service performance in various conditions, including dry hot air, neutral salt spray, sand abrasion, and heat/synthetic seawater salt spray/high humidity cycle tests. The dry hot air test results indicate that the SERMETEL coating is less thermally aggressive than the sandblasted SERMETEL coating, but neither can withstand prolonged high temperatures.After 3000 hours of neutral salt spray testing, the corrosion of the coatings became progressively worse. The coating is heavily corroded at the fork. The abrasion resistance of the SERMETEL coating and the sandblasted SERMETEL coating were 13.29 L/μm and 10.45 L/μm, respectively. The results of heat resistance/synthetic sea salt spray/high humidity cycling test for the two coatings under composite conditions show that after the compound alternating effects of sea salt spray, high temperature and high humidity, the two coatings did not show corrosion expansion or peeling off phenomenon at the scratching point. It shows that the two coatings have high corrosion resistance to seawater salt spray, high temperature and high humidity under composite cycling conditions. This paper has an important evidence for the future application of metal coating in seawater corrosion prevention.