Structural and phase transformations and rate of Ti2Co and TiCo interaction with hydrogen and synthesis of nondestructive nanostructured titanium hydride composites

• Published in: Powder metallurgy and metal ceramics 2012-11, Vol.51 (7-8), p.474-484
• Main Authors: Bratanich, T. I., Kucheryavyi, O. V., Skorokhod, V. V., Kopylova, L. I., Kotko, A. V., Krapivka, M. O.
• Format: Article
• Language: English
• Subjects: Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Glass; Materials Science; Metallic Materials; Natural Materials
• ISSN: 1068-1302; 1573-9066
• DOI: 10.1007/s11106-012-9457-7

The paper examines the sequence of structural and phase transformations and the rate of Ti 2 Co and TiCo interaction with hydrogen. Destructive hydrogenation of Ti 2 Co is used to produce nondestructive nanostructured titanium hydride composites. Thermodynamic analysis has shown that Ti 2 Co and TiCo destructive hydrogenation is thermodynamically favored in the temperature range 298–973 K. In the temperature range 773–973 K, Ti 2 Co interacts with hydrogen by destructive hydrogenation reaction, in which hydrogen is dissolved in the intermetallic compound, titanium is selectively hydrogenated to cubic TiH 1.9 , and titanium-depleted TiCo and TiCo 2 intermetallics are successively formed in accordance with the Ti–Co phase diagram. The rate of Ti 2 Co destructive hydrogenation is proportional to temperature, hydrogen pressure, and surface area of the starting samples. Compound TiCo is hydrogenated to form a solution of hydrogen in Ti 1+y Co, intermetallic TiCo 2 , and a solution of hydrogen in β-titanium. Nondestructive composites with nanostructured components are synthesized by Ti 2 Co destructive hydrogenation.