Investigação do desempenho da superliga Inconel 713C revestida com NiCrAlY sob oxidação de 850 a 1200 °C

Abstract

Nickel-based superalloys may present better oxidation resistance in their respective operation temperatures if MCrAlY-type coatings are previously applied to them. Thus, the present research investigated the high temperature performance of the Inconel 713C nickel superalloy coated with a NiCrAlY layer, deposited by the laser cladding technique with pre-deposited powder. The samples were submitted to isothermal oxidation in muffle furnaces at the temperatures of 850, 900, 1000 and 1200 °C for 15 hours. The coating effectiveness was evaluated using the standardized weight gain technique, SEM/EDS chemical composition analyses and optical microscopy. The deposition of the coating by laser cladding was able to reduce the oxidation rate by 53% at the temperature of 850 °C and by 27% for temperatures up to 1000 °C. However, there was intense degradation of the coating at the temperature of 1200 °C.