FEATURES OF HIGH-TEMPERATURE OXIDATION OF HIGH-ENTROPY AlCrFe₃CoNiCu ALLOY

Abstract

The features of scale formation on the AlCrFe₃CoNiCu alloy during oxidation at 900 °C for 50 h and the effect of high-temperature annealing on structural and phase transformations of the alloy matrix and its mechanical properties were examined. It is found that long-term annealing at 900 °C leads to the formation of a three-phase alloy consisting of a solid solution with bcc lattice of B2 structural type and two solid solutions with fcc crystal lattice (one of them contains a higher amount of Ni and Co, and the other is a solid solution enriched with 66 wt.% Cu). A two-phase scale containing Al₂O₃ and CuO formed on the alloy surface in oxidation. The stability of the AlCrFe₃CoNiCu alloy mechanical properties was determined by the indentation method after long-term high-temperature oxidation.