“…This Ni-based superalloy is used in components such as automotive turbochargers, aerospace engines, diesel engines, and gasoline engines [12,13]. Due to chemical similarities, the replacement of Ta by Nb was recently proposed by our group, leading to the development of an experimental superalloy called Nb-modified MAR-M246 [3,6,7]. Alkmin et al [13] studied both MAR-M246(Ta) and MAR-M246(Nb) for pseudo-isothermal oxidation tests at temperatures of 800, 900, and 1000 • C. For 800 and 900 • C, the experiments were performed for up to 1000 h, and for 1000 • C, they had a duration of 650 h. At 800 • C, these superalloys had very similar behavior, showing good oxidation resistance and paraboliclike curves, and also the same oxide products.…”