Hostname: page-component-78c5997874-s2hrs Total loading time: 0 Render date: 2024-11-09T14:25:05.708Z Has data issue: false hasContentIssue false
  • English
  • Français

Corrosion Rate of Unalloyed Steels and Cast Irons in Reducing Granitic Groundwaters and Chloride Solutions

Published online by Cambridge University Press:  28 February 2011

J. P. Simpson ,
R. Schenk  and
B. Knecht
J. P. Simpson
Affiliation:
Sulzer Bros Ltd., Winterthur, Switzerland
R. Schenk
Affiliation:
Sulzer Bros Ltd., Winterthur, Switzerland
B. Knecht
Affiliation:
National Cooperative for the Storage of Radioactive Waste (NAGRA), Baden, Switzerland
Get access

Abstract

Measurements of the corrosion rate of unalloyed steel have been made under conditions representative for repositories in the granitic bedrock of Northern Switzerland using two independent methods: (1) Immersion tests in two representative groundwaters, with and without bentonite; (2) Hydrogen evolution measurements in these groundwaters. The immersion tests were carried out at 80°C and 140°C. In both cases the corrosion rate was higher than 50 μm/a as determined at the end of the first observation period of about 500 h. Corrosion rates of under 10 μm/a were estimated after the first 500 h. The corrosion rates were similar in both groundwaters with mineralisations of approx. 3 g/11 and 14 g/11 respectively, and were generally higher at 80°C than at 140°C. The hydrogen evolution measurements allow an hourly determination of the corrosion rate, with a sensitivity expressed as a corrosion rate of better than 0.1 μm/a. The results generally confirm the observation made in the immersion testing; high corrosion rates were observed over the first few days but then decreased to values well below 10 μm/a. The steady state corrosion rates measured were 1.1 μm/a, 6.5 μm/a, and 2.5 μm/a at 25°C, 50°C, and 80°C respectively in the water with the higher mineralisation. The inverse temperature effect on corrosion rate above 50°C is attributed to a change in the nature of the passive film at higher temperatures.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 50: Symposium STOCKHOLM – Scientific Basis for Nuclear Waste Management IX , 1985 , 429
Copyright
Copyright © Materials Research Society 1985

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

List of References

1. Gewähr, Nagra Report NGB 85−04, Baden, Switzerland, 1985 Google Scholar
2. Simpson, J.P., Nagra Technical Report Series NTB 83−05, Baden, Switzerland, 1983 Google Scholar
3. Simpson, J. P., Nagra Technical Report Series NTB 84−01, Nagra, Switzerland, 1984 Google Scholar
4. Grauer, R., Nagra Technical Report Series NTB 84−19, Baden, Switzerland, 1984 Google Scholar
5. Nagra Technical Report Series NTB 84−32, Baden, Switzerland, 1984 Google Scholar
6. Swiss standard VSM 10697. Verband Schweizerischer Maschinen-industrieller, 1976 Google Scholar
7. DIN Standard 1693. Deutsches Institut für Normung, 1973 Google Scholar
8. Müller-von, Moos M., Kahr, G., Nagra Technical Report Series NTB 83−12, Baden, Switzerland, 1983 Google Scholar
9. Schenk, R., Nagra Technical Report Series NTB 83−16, Baden, Switzerland, 1983 Google Scholar
10. Marsh, G. P., Bland, I. W., Desport, J. A., Naish, C., Westcott, C., Taylor, K. J., European Appl. Res. Rept.-Nucl. Sci. Technol. 5 (2), 223–252, 1983 Google Scholar
11. STEAG Kernenergie GmbH, Motor-Columbus Ingenieurunternehmung AG, Nagra Technical Report Series NTB 84−31, Baden, Switzerland, 1984 Google Scholar
12. Wick, W.: Final storage container designs for highly radioactive waste. Poster paper presented at this conference and to be published.Google Scholar