High-temperature oxidation behaviour of high chromium superalloys additively manufactured by conventional or extreme high-speed laser metal deposition

Abstract In this paper, the high-temperature oxidation behaviors at 900 °C of the conventional laser metal deposition (LMD) and extreme high-speed laser metal deposition (EHLMD) high chromium K648 superalloys were comprehensive studied. The experimental results reveal that the oxidation resistance of the LMD K648 superalloy is better than the EHLMD K648 superalloy. The oxidation films of LMD and EHLMD K648 superalloy consists of continuous Cr2O3 film and an internal wedge-shaped Al2O3. The oxidation process is mainly controlled by the outward diffusion of oxide-forming elements and the inward penetration of oxygen.