Research on the Antioxidant Property of MCrAlY Alloy Powders

CoNiCrAlY powders with similar chemical compositions but different oxygen contents were prepared by vacuum inert gas atomization. Their oxidation behaviors at 1000 °C were investigated by mass gain and oxidation rate measurements, X-ray diffraction, scanning electron microscope and energy dispersive spectrometer. Results show that the oxidation rate of mass gain increases obviously with the increase of time; their relationship is linear at the former stage and parabolic at the later stage. The formed oxide of Al2O3 was detected by XRD. The intensity of its diffraction peak becomes stronger with the increase of time. The oxidation resistance of the powder depends on the concentration gradient of oxygen.