Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-03T00:58:16.328Z Has data issue: false hasContentIssue false

Effect of Anions on the Fluoride Corrosion of Titanium-Grade 7

Published online by Cambridge University Press:  11 February 2011

A. L. Pulvirenti
Affiliation:
The Catholic University of America, Washington, D.C. 20064
K. M. Needham
Affiliation:
The Catholic University of America, Washington, D.C. 20064
M. A. Adel-Hadadi
Affiliation:
The Catholic University of America, Washington, D.C. 20064
D. S. Wong
Affiliation:
The Catholic University of America, Washington, D.C. 20064
A. Barkatt
Affiliation:
The Catholic University of America, Washington, D.C. 20064
C. R. Marks
Affiliation:
Dominion Engineering, Inc., 11730 Plaza America Drive, Reston, VA 20190
J. A. Gorman
Affiliation:
Dominion Engineering, Inc., 11730 Plaza America Drive, Reston, VA 20190
Get access

Abstract

The effects of chloride, sulfate, and nitrate on the fluoride ion local attack of Ti-Grade 7 (Ti-7: UNS R52400) were investigated. It was observed that a chloride: fluoride ratio of as high as 10 : 1 by mole was necessary to produce visible severe attack in immersion tests. Localized attack on Ti-7 was most severe at approximately 120°C, and at neutral pH. However, electrochemical studies detected that a narrowing of the passive region can occur at chloride: fluoride ratios as small as 1.1 : 1 by mole. The addition of sulfate did not significantly inhibit pitting or stress corrosion cracking of Ti-7 U-bends. However, the addition of nitrate is suspected to act as an effective inhibitor.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Brossia, C. S. and Cragnolino, G. A., “Effects of Environmental, Electrochemical, and Metallurgical Variables on the Passive and Localized Dissolution of Ti-Grade 7”, Paper No. 211, Corrosion/2001, NACE International, Houston, TX, 2001.Google Scholar
2. Pulvirenti, A. L., Needham, K. M., Adel-Hadadi, M. A., Barkatt, A., Marks, C. R. and Gorman, J. A., “Corrosion of Titanium Grade 7 in Solutions Containing Fluoride and Chloride Salts”, Paper No. 2552, Corrosion/2002, NACE International, Houston, TX, 2002.Google Scholar
3. Rosenberg, N. D., Gdowski, G. E. and Knauss, K. G., “Evaporative Chemical Evolution of Natural Waters at Yucca Mountain, Nevada”, Appl. Geochem., 16, 12311240 (2001).Google Scholar
4. Harrar, J. E., Carley, J. F., Isherwood, W. F. and Raber, E., “Report of the Committee to Review the Use of J-13 Well Water in Nevada Nuclear Waste Storage Investigations“, Lawrence Livermore National Laboratory Report No. UCID-21867, Livermore, CA, 1990.Google Scholar
5. Frenier, W. W., Technology for Chemical Cleaning of Industrial Equipment Houston, NACE Press, 2001.Google Scholar
6. Shoesmith, D.S., private communication.Google Scholar
7. Gdowski, G.E., “Degradation Mode Survey Candidate Titanium – Base Alloys for Yucca Mountain Project Waste Package Materials,” Lawrence Livermore National Laboratory, December 1997.Google Scholar