Enhancement of the Corrosion Resistance of Mild Steel in Marine Applications

This study aims to improve mild steel's corrosion resistance in marine applications. Mild steel has low corrosion resistance, especially in salty conditions, so enhancing this property is required. This study aims to increase the corrosion resistance of mild steel by heat treatment processes. The specimens were heated to the temperature of 800°C, then the specimens were separated into two groups, specimens of both of the groups cooled inside a furnace (annealing), cooled in air to room temperature (normalizing), and cooled in water (quenching), then the first group of specimens was immersed in salinity of (33.9) ppt for 45 days, and the other group of specimens was immersed in salinity of (37.8) ppt for 45 days. The corrosion resistance is determined experimentally by the weight loss method, with the consideration of the effect of each parameter, such as salinity and cooling rate. The results obtained showed that corrosion resistance in the quenching process is higher than in other cooling processes in both salinities, followed by annealing and normalizing processes. In which the weight loss of the quenched specimen was (0.0057) g in a salinity of (33.9) ppt, while it was (0.0072) g in (37.8) ppt.