Corrosion problems in waste incinerators are usually very severe, also due to the presence of low-melting point heavy and alkali metal chlorides. In this paper, the corrosion behavior of several Fe-based alloys with different Cr content, as well as three pure metals Fe, Cr, and Ni, was studied at 450°C beneath ZnCl2-KCl deposits in flowing pure oxygen. All the materials suffered from accelerated corrosion, characterized by an important separation and spaUation of the oxide scales. The
Cr-containing alloys did not exhibit better corrosion resistance to this environment due to the poor adherence of the scales to the matrix, while
higher Ni content could improve the corrosion resistance. Chlorine was always enriched on the substrate surface beneath the scale, and in some cases chlorine-rich corrosion products were also present within the alloy matrix. For the HP stainless steel, Cr-rich Cr7C3 carbides were
preferentially attacked in comparison to the matrix. The effect of Cr is discussed with respect to the nature of the scales.
Keywords: Fe; Cr; Ni; Fe-based alloy; Waste Incineration; Chloride melts; Corrosion