Short Time Oxidation Behavior of a Ni-Based Single Crystal Superalloy at High Temperature

Short time (less than 16 h) oxidation behavior of a Ni-based single crystal superalloy at high temperatures was studied by scanning electron microscopy and X-ray diffraction. The results show that the oxidation rate increased with the increase of oxidation temperature and time when the tested alloy was oxidized at 900-1 100 ℃ in air. The oxidation products were comprised of Al2O3, NiO, Cr2O3 and TiO2 after the alloy was oxidized at 900 ℃ for 16 h, and the oxidation film with low compact was incomplete. After the alloy was oxidized at 1 000 ℃ for 16 h, the complete and compact oxidation film of Cr2O3 and Al2O3 was formed. After the alloy was oxidized at 1 100 ℃ for 16 h, the bulk NiCr2O4 with spinelle structure were obtained, and the partial oxidation film was loosener and with part dropping.