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Ni-Cr alloy cladding layers with Cr contents of 10wt%, 20wt%, and 40wt% were prepared by laser melting technique and their high temperature oxidation characteristics at 900 °C and hot corrosion characteristics in Na₂SO₄+25wt% K₂SO₄ mixed salt at 600 °C were investigated. The results show that the Cr content plays a key role in the high temperature characteristics of cladding layers. Increasing the Cr content is more effective in improving the resistance of cladding layers to sulfate-induced hot corrosion than in improving the resistance to cyclic high-temperature oxidation. Cr40 provides the best resistance to high-temperature oxidation and hot corrosion. The oxidation products of Cr10 are dominated by NiO, which is extremely easy to shed and the internal oxidation is serious. Although a single Cr₂O₃ layer can be formed on the Cr40 surface, cracking within the Cr-rich oxides caused by thermal and growth stresses renders the resistance of Cr40 to cyclic high-temperature oxidation only slightly better than that of Cr20. Suffering from hot corrosion, the surface of Cr10 presents lamellar NiO and Ni₃S₂ stacked distribution of corrosion products, and Ni sulfide is also generated in the inner corrosion zone. The Cr₂O₃ layer on Cr20 surface is destroyed, and internal corrosion is severe, generating CrS. A dense protective Cr₂O₃ layer is generated on Cr40 surface, efficiently preventing further corrosion.