High-Temperature Oxidation of ZrB2–MoSi2–AlN Composite Ceramics

• Published in: Powder metallurgy and metal ceramics Vol. 58; no. 1-2; pp. 99 - 103
• Main Authors: Grigoriev, O. N., Panasyuk, A. D., Podchernyaeva, I. A., Neshpor, I. P., Yurechko, D. V.
• Format: Journal Article
• Language: English
• Published: New York Springer US 15.06.2019; Springer Nature B.V
• Subjects: Aluminum nitride; Aluminum oxide; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Cristobalite; Diffusion barriers; Diffusion layers; Glass; High temperature; Materials Science; Metallic Materials; Molybdenum disilicides; Molybdenum oxides; Molybdenum trioxide; Natural Materials; Oxidation; Phase composition; Refractory materials; Scale (corrosion); Silicon dioxide; Solid solutions; Zirconium compounds; Zirconium dioxide; molybdenum disilicide; ceramics; aluminum nitride; zirconium diboride; high-temperature oxidation
• ISSN: 1068-1302; 1573-9066
• DOI: 10.1007/s11106-019-00052-5

The oxidation mechanism of ZrB 2 –MoSi 2 –AlN composite ceramics has been studied in the range 1550–1680°C. The oxidation stages and scale structure and phase composition have been established. Two main scale layers have been found. The outer layer forms at ~1550°C. It consists of SiO 2 (β-cristobalite) and an Al 2 O 3 –SiO 2 solid solution containing MoO 3 . At 1680°C, a layer of crystalline zirconium dioxide grains forms at the boundary with the initial ceramic surface. This layer is an effective protective barrier for oxygen diffusion into the sample.