High Temperature Oxidation Behavior of CrMnFeCoNi High-Entropy Alloy

High temperature oxidation behavior of CrMnFeCoNi high-entropy alloy was investigated in oxygen at 600-1100°C by thermogravimetric technique. The composition each element is 20 at% an experimental alloy. Oxidation rates observed mass change measurement were generally smaller comparison to those single element. values gains slight larger against pure Ni or Ni-based superalloys the same temperatures oxygen. Mass gain curves almost obeyed on parabolic rate law, and had magnitudes as increased. X-ray diffraction analysis revealed that scale formed alloys consisted Mn2O3 Cr2O3. Although Mn originally has a rate, relatively small because protective nature Fe-Cr spinel oxide film. One reasons considered from viewpoint thermodynamics Cr have negative Gibbs free energy reaction among five elements