| Summary: | Alloys based on NiAl-Cr-Co (<i>base</i>) with complex dopants (<i>base+2.5Mo-0.5Re-0.5Ta, base+2.5Mo-1.5Re-1.5Ta, base+2.5Mo-1.5Ta-1.5La-0.5Ru, base+2.5Mo-1.5Re-1.5Ta-0.2Ti, base+2.5Mo-1.5Re-1.5Ta-0.2Zr</i>) were fabricated by centrifugal SHS metallurgy. The phase and impurity compositions, structure, mechanical properties, and the mechanism of high-temperature oxidation at T = 1150 °C were studied; the kinetic oxidation curves, fitting equations and parabolic rate constant were plotted. Al<sub>2</sub>O<sub>3</sub> and Co<sub>2</sub>CrO<sub>4</sub> were the major phases of the oxidized layer. Three layers were formed: I—the continuous Al<sub>2</sub>O<sub>3</sub> layer with Co<sub>2</sub>CrO<sub>4</sub> inclusions; II—the transitional MeN-Me layer with AlN inclusions; and III—the metal layer with AlN inclusions. The positive effect of thermo-vacuum treatment (TVT) on high-temperature oxidation resistance of the alloy was observed. The total weight gain by the samples after oxidative annealing decreased threefold (from 120 ± 5 g/m<sup>2</sup> to 40 ± 5 g/m<sup>2</sup>). The phases containing Ru and Ti microdopants, which reduced the content of dissolved nitrogen and oxygen in the intermetallic phase to the values ∑<sub>O, N</sub> = 0.0145 wt.% for the <i>base+2.5Mo-1.5Ta-1.5La-0.5Ru</i> alloy and ∑<sub>O,N</sub> = 0.0223 wt.% for the <i>base+2.5Mo-1.5Re-1.5Ta-0.2Ti</i> alloy, were identified by transmission electron microscopy (TEM). In addition, with the significant high-temperature oxidation resistance, the latter alloy with Ti had the optimal combination of mechanical properties (σ<sub>ucs</sub> = 1644 ± 30 MPa; σ<sub>ys</sub> = 1518 ± 25 MPa).
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