Structural Transformations of Ceramics Forming during High-Temperature Nitridation of Zr–Nb Alloys

• Published in: Inorganic materials 2022-05, Vol.58 (5), p.531-537
• Main Authors: Kovalev, I. A., Shevtsov, S. V., Kochanov, G. P., Fedorov, S. V., Kannykin, S. V., Sitnikov, A. I., Ogarkov, A. I., Shokod’ko, A. V., Strel’nikova, S. S., Chernyavskii, A. S., Solntsev, K. A.
• Format: Article
• Language: English
• Subjects: Ceramics; Chemistry; Chemistry and Materials Science; Composite structures; Heterostructures; High temperature; Industrial Chemistry/Chemical Engineering; Inorganic Chemistry; Materials Science; Niobium base alloys; Porosity; Solid solutions
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1134/S0020168522050065

— We describe a sequence of structural transformations characterizing high-temperature nitridation of zirconium–niobium alloys containing 0.1–10 wt % niobium. High-temperature saturation of solid solutions of niobium in zirconium with nitrogen is accompanied by decomposition of the Zr〈Nb〉 solid solution and the formation of Zr 1 – х Nb х N–(ZrN 1 – n /β-solid solution of Zr in Nb)–Zr 1 – х Nb х N composite structures. During nitridation of the heterostructures, zirconium nitride reacts with β-niobium, which is the final step of the nitridation of the parent Zr〈Nb〉 solid solution. Characteristically, the ceramics thus prepared have near-surface porosity reproducing the surface porosity of the as-rolled material.