Corrosion rate analysis on the paint coated-A36 steel in salt and acid solutions

Steel resistance is widely required to support most industrial processes. However, to date, numerous marketed steel plates are susceptible to corrosion, especially in the air or in the water environment. This study utilizes the weight loss method to obtain the corrosion rate value on steel, coated with paint, further analyzed for the corrosion rate values respectively by applying 5% NaCl solution and 5% HCl solution. In this study, to obtain differences in the effect of time on the corrosion rate, variations in immersion time are added for 6, 12, 18, 24, and 30 days. HCl solution presents a higher corrosion rate than in NaCl solution on coated steel. HCl solution presents the highest average corrosion rate on the 6th day of 1078.405 mm/y and the lowest corrosion rate on the 30th day of 323.95 mm/y. Meanwhile, NaCl demonstrates the highest average corrosion rate on the 30th day of 13. 701 mm/y and the lowest corrosion rate on the 6th day of 5.016 mm/y. In the immersion of steel with NaCl solution, the increase in immersion time greatly affects the corrosion rate of the steel. In addition, the corrosion rate increases along with the increasing immersion time, meanwhile the results in HCl solution are the opposite.