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Three nickel-based powder superalloys FGH4113A (WZ-A3), FGH96 and FGH97 were subjected to oxidation tests in air at 815, 900 and 1000℃. Static weight gain method was used to determine the oxidation dynamics curve of the alloys at different temperatures and to evaluate the oxidation resistance. The surface and cross-sectional morphology, composition and structure of specimens were analyzed after oxidation tests by X-ray diffraction, scanning electron microscopy, energy spectrometer. The results showed that the three alloys were completely antioxidant grade at 815 and 900℃, WZ-A3, FGH96 and FGH97 were antioxidant grade, secondary antioxidant grade and complete antioxidant grade respectively at 1000℃.The oxide layers of WZ-A3 and FGH96 alloys were similar after oxidation at a high temperature of 1000℃, which consisted of an outermost layer TiO2, a middle layer mixed layer of Cr2O3 and a small amount of TiO2, an innermost layer was dendritic Al2O3. There was the enrichment of Nb and Mo elements at the boundary between the middle and the innermost layer for WZ-A3. The difference in oxidation properties of the three alloys was related to Al content. Al content was low in WZ-A3 and FGH96 and the dendritic Al2O3 layer formed can’t effectively form isolation. After the Cr2O3 reaction, it evaporated to form holes, which destroys the density of the oxide layer at high temperatures. Al content in FGH97 was high such that the formation of a dense Al2O3 layer on the surface can effectively block the outward diffusion of other alloying elements after oxidation at 1000℃, so the FGH97 exhibited excellent oxidation resistance. The addition of 1.0wt%Ta and 1.2wt%Nb has improved the oxidation resistance of WZ-A3 alloy to a certain extent.