High-temperature oxidation behavior of GH4169 superalloy repair by wire-fed electron beam directed energy deposition

This study systematically examines the high-temperature oxidation behavior of GH4169 nickel-based superalloy repaired via wire-fed electron beam directed energy deposition (EB-DED). The analysis focuses on two distinct regions: the deposited zone and substrate zone. After exposure to 850 degrees C for 120 h, the oxidation films consisted of an outer layer of Cr2O3 and an inner layer of Al2O3 and TiO2. The deposition zone exhibits lower oxidation resistance, attributed to more pronounced element segregation resulting from the EB-DED process condition. This investigation establishes a clear correlation between element segregation and oxidation resistance, demonstrating that severe element segregation leads to poor oxidation resistance.