Effect of nitrogen on the oxidation behavior of Ti3Al-based intermetallic alloys

Roy, T. K. ; Balasubramaniam, R. ; Ghosh, A. (1996) Effect of nitrogen on the oxidation behavior of Ti3Al-based intermetallic alloys Metallurgical and Materials Transactions A, 27 (12). pp. 4003-4010. ISSN 1073-5623

Full text not available from this repository.

Official URL: http://www.springerlink.com/content/p470823u7t1006...

Related URL: http://dx.doi.org/10.1007/BF02595649

Abstract

The effect of nitrogen on the oxidation behavior of Ti-25Al, T-24Al-15Nb, and Ti-25Al-11Nb (at. pct) has been examined in this study. The gases employed were nitrogen and oxygen-nitrogen and oxygen-argon mixtures in various proportions at a total pressure of 1 atmosphere. The experiments were carried out in the temperature range of 1100 to 1300 K by thermogravimetry. The suitability of employing the parabolic rate law as the basis of interpretation of weight gainvs time data has been discussed. Oxidation resistance of Nb-containing alloys was superior to that of binary Ti-25Al, irrespective of the gas composition employed. The nitridation rates of alloys, with or without Nb, were more than an order of magnitude lower than those for oxidation. The scales were characterized by X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive X-ray (EDX) analysis. The scales formed in all the conditions mostly consisted of TiO2 and Al2O3. However, TiN was observed in scales of Nb-containing alloys in all nitrogen bearing gases and seemed to primarily account for improved oxidation resistance of the preceding in comparison to alloys without Nb. Nitrogen pretreatment was provided for some samples before oxidation for further elucidation of the role of nitrogen.

Item Type:Article
Source:Copyright of this article belongs to The Minerals, Metals & Materials Society.
ID Code:61375
Deposited On:15 Sep 2011 03:40
Last Modified:15 Sep 2011 03:40

Repository Staff Only: item control page