Hostname: page-component-77c89778f8-gq7q9 Total loading time: 0 Render date: 2024-07-17T20:56:59.440Z Has data issue: false hasContentIssue false
  • English
  • Français

Method for Analyzing Nitrogen in Titanium Alloys

Published online by Cambridge University Press:  14 March 2018

Mary Mager
Mary Mager*
Affiliation:
University of British Columbia

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Careful analysis of the composition of the titanium alloys is a very critical part of the overall quality control of all components in modern jet aircraft engines. The engine manufacturing industry is seriously striving for a zero defect rate, which is a very difficult goal indeed. This control is made more difficult by the very reactive nature of titanium when it is heated to its melting point. Titanium reacts with the nitrogen and oxygen in the air to form brittle refractory compounds, so it must be melted and refined in a vacuum. Once these refractories are formed they are very difficult to find or remove and they form the basis for brittle zones in the alloy that can be the initiation site for cracks under the high stress loads found in a jet engine. The presence of nitrogen, in particular, causes a defect called a "hard-aipha", which is an area of nitrogen enrichment containing three to eight percent nitrogen and having a hardness three times that of the alloy.

Type
Research Article
Information
Microscopy Today , Volume 7 , Issue 6 , August 1999 , pp. 8 - 11
Copyright
Copyright © Microscopy Society of America 1999

References

1. Bellot, J-P. and Mitchell, A.. “Hard Alpha Particle Behaviour in a Titanium Alloy Liquid Pool.” Light Metals 1994, ed. J. P. Kipouros, publ. TMS-AIME.320 - 328.Google Scholar
2. Bellot, J-P., et al. “The Formation and Removal of Hard- Alpha” Material during the Melting of Titanium Alloys“ Titanium ” 95, eds. Froes, F. H. and Caplan, I. L., publ. TMS-AIME 1995 pp. 1454-1461.Google Scholar
3. Bohntng, J. E., “Microprobe examination of Nitrogen and/or Oxygen Contamination in Titanium Alloys,” Microbeam Analysis- 1985, 197.Google Scholar
4. Bastin, G. F. and Heijligers, H. J. M., “Quantitative Electron- Probe Microanalysis of Very Light Elements,” Microbeam Analysis—1985, 1.Google Scholar