Influence of surface preparation on the corrosion of steels in simulated waste incineration environments

In order to study the corrosion behaviour of stainless steels on the base of Fe-18Cr-10Ni were conducted in a simulated waste incineration atmosphere discontinuous exposures. Especially the influence of surface preparation and also the influence of alloying elements on the corrosion were of interest. Therefore different surface preparations as sandblasting, grinding and electropolishing were applied to the samples before exposure. The experiments were carried out in a N2-5%O2-2.5%H2O-0.05%HCl-0.05%SO2 atmosphere at 600DGC with the samples embedded in fly ash from a waste incineration plant. In addition thermogravimetric experiments were conducted in a He-5%O2-0.05%HCl atmosphere at 600DGC without fly ash using a microbalance. Analysis of the corrosion products was performed after the experiments by scanning electron microscopy with EDX and X-ray analysis. The metal losses of the samples were determined after removing the corrosion scale.