Effect of molten salt treatment on descaling behavior of 410 SS in sulfuric acid solution

The effect of molten salt treatment on the modification of scale properties of annealed 410 SS and subsequent descaling behavior in sulfuric acid was investigated. The experimental results showed that the scale formed on annealed 410 SS was mainly composed of (Cr, Fe)3O4 and Cr2O3. After molten salt treatment, only Fe3O4, was found remained on the surface. Potential decay was noticed during pickling in sulfuric acid, which was associated with the scale removing process. Furthermore, the activation time (τ) required for complete descaling decreased with increasing concentration and temperature of sulfuric acid.