Hot Corrosion Behavior of Some Superalloys in a Simulated Incinerator Environment at 900 °C

Incinerators are being used to burn solid waste of all types. This burning of waste creates a very aggressive environment at extremely high temperature. This environment attacks the various components of the incinerators. Some studies have been reported regarding behavior of steels in simulated incinerator environment at 550 °C. In present work superalloys Superco 605, Superni 600, and Superni 718 have been subjected to cyclic oxidation in 40 wt.% K₂SO₄ + 40 wt.% Na₂SO₄ + 10 wt.% KCl + 10 wt.% NaCl environment at 900 °C under cyclic condition. Weight change measurements have been done and weight change has been plotted against the numbers of cycles. The oxide scales formed on the surface of the corroded superalloys have been characterize by FESEM, EDS, XRD, cross-sectional analysis, and x-ray mapping. The nickel-based superalloys Superni 600 and Superni 718 indicated better resistance to corrosion in the above environment whereas Superco 605 lead to massive weight gain.