High temperature oxidation behavior of Mo-Zr alloys in pure oxygen condition

• Published in: International journal of refractory metals & hard materials 2024-11, Vol.124, p.106820, Article 106820
• Main Authors: Jiang, Shuwen, Che, Xuezhen, Huang, Junkun, Huang, Dandan
• Format: Article
• Language: English
• Subjects: EPMA; Mo-Zr as-cast alloys; Multi-layer; Oxidation; XPS
• ISSN: 0263-4368
• DOI: 10.1016/j.ijrmhm.2024.106820

In the current study, alloys of Mo-95Zr, Mo-80Zr, Mo-50Zr, Mo-35Zr, Mo-20Zr and Mo-3Zr (at. %) were prepared to investigate the microstructure and oxidation behaviors of the whole composition range of Mo-Zr as-cast alloys. Laves, (Zr) and/or (Mo) intermetallic phases were presented in the primary dendrite, eutectic or peritectic structures in the prepared alloys. The isothermal oxidation process was accompanied by the formation of multi-layer, consisting of the porous and loose ZrO2 and MoO3, which was individually changed from the (Zr), Laves and (Mo). The specimens were examined using a combination of gravimetry and several surface-analytical techniques, including X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscope and electron microprobe. Phases composition on the microstructure and oxidation behavior, and the sources of internal stress and defects formation in oxide layer on these alloys during oxidation have been discussed. •The oxidation performance and corrosion mechanism of Mo-Zr alloys in low oxygen activities environment were investigated.•Zr-rich samples show parabolic decay under isothermal conditions, others linear mass loss over time.•The oxide layers displayed a poor oxidation resistance and all absence of the protective characteristic.•The formation of pores, cracks and defects in the oxide scales is a mixture of many factors.