Study on high temperature stability of inconel 625 surfacing alloys

Thermal power generation is the main way of power generation in China. Inconel 625 alloy is widely used in steam turbine blades due to its excellent high temperature performance. In the face of high temperature environment, long-term service will lead to the failure of Inconel 625 alloy. The repair of Inconel 625 alloy after failure is the most economical way, but the research on the repaired Inconel 625 surfacing alloy is still in its infancy. In this paper, Inconel 625 surfacing alloy was prepared by surfacing process, and the oxidation behavior of Inconel 625 surfacing alloy at 600 °C–800 °C for different oxidation time was studied. The results show that the corrosion rate of Inconel 625 surfacing alloy was 0.038 mm year−1, and the surfacing alloy can reach grade 4 corrosion resistance, which was applied in practical engineering. The oxides formed on the surface of the surfacing alloy were mainly Cr2O3, NiO and MoO3. From the outside of the oxide layer to the substrate, the content of NiO decreases and the content of Cr2O3 increased. The oxidation was mainly completed by the diffusion of O.