|About this Abstract
||2019 TMS Annual Meeting & Exhibition
||Coatings and Surface Engineering for Environmental Protection
||Effect and Role of Alloyed Nb on the Air Oxidation Behaviour of Ni-Cr-Fe Alloys at 1000 °C
||Yaxin Xu, Wenya Li
|On-Site Speaker (Planned)
This study aims to focus on the effect of alloyed Nb on the high-temperature oxidation behaviour of Ni-based alloys. Ni-Cr-Fe based alloys alloyed with Nb (0, 1 and 2 wt.%) were designed and their static oxidation behaviour was evaluated at 1000 °C up to 100 h. The mass gain of alloys during corrosion test was recorded to determine oxidation kinetics, and the morphology and structure of oxide scales after oxidation were characterised by SEM, XRD and EPMA. Results reveal that the alloyed Nb has a positive impact on both the oxidation kinetics and oxide scales. The parabolic rate constant kp of Nb-alloyed Ni-25Cr-15Fe alloys are nearly one-fourth the value for Nb-free alloy. The oxide scales change from spinel-included multi-layers in the Nb-free alloy to a much thinner Cr2O3 single-layer in the Nb-alloyed alloys. NbC precipitates and slightly dissolved Nb account for these changes.
||Planned: Supplemental Proceedings volume