Effect of Chloride Concentration on the Corrosion Rate of Maraging Steel

The corrosion behavior of Maraging steel has been studied by using different techniques, including open circuit potential and polarization measurements in addition to microstructure examination such as optical microscopy and XRD (X-Ray Diffraction) investigation. The corrosion behavior of Maraging steel has been examined in sodium chloride solutions with different concentrations from 0.1 M to 2 M. It was found that the corrosion resistance of Maraging steel is inversely proportional with the concentration of sodium chloride solution. The corrosion resistance is directly proportional to the Mo and Ti content in the Maraging steel. Heat treatment of the Maraging steel improved its mechanical properties with no effect on the corrosion behavior as the precipitation of inter-metallic compounds leading to some galvanic action. However, sample IV having lower Mo content than sample V showed after heat treatment an improvement in the corrosion resistance.