High-temperature oxidation of inconel 617 at 850 ~ 1050 °c

High temperature oxidation behavior of superalloy Inconel 617 (In-617) was studied over the temperature range of 850 ~ 1050 °C in dry air. The results showed that the oxidation kinetics followed a parabolic-rate law, and the oxidation rates increased steadily with temperature. In general, duplex scales formed on the alloy consisted mostly of Cr₂O₃ and NiCr₂O₄ in the outer layer, and of a single Cr ₂O₃ layer in the inner layer. In addition, the internal oxidation of Al₂O₃ precipitates was observed at the substrate beneath the scales, of which the amount increased with increasing temperature.