Hostname: page-component-586b7cd67f-t7czq Total loading time: 0 Render date: 2024-11-24T18:37:46.129Z Has data issue: false hasContentIssue false

Corrosion Rates of Zircaloy-4 by Hydrogen Measurement under High pH, Low Oxygen and Low Temperature Conditions

Published online by Cambridge University Press:  19 April 2012

Tsutomu NISHIMURA
Affiliation:
Kobe Steel, Ltd., 4-7-2 Iwaya-Nakamachi, Nada-ku, Kobe 657-0845, Japan
Tsuyoshi TATEISHI
Affiliation:
Kobelco Research Institute, Inc., 1-5-5 Takatsukadai, Nishi-ku, Kobe 657-2271, Japan
Get access

Abstract

Corrosion tests of Zircaloy-4 were performed in a dilute NaOH solution (pH =12.5) at 303 K for 90 days using the gas flow system (oxygen; < 1 ppb) and a batch method (oxygen; < 0.1 ppm). The corrosion rate was determined by measuring gaseous hydrogen and the hydrogen absorbed into Zircaloy-4 assuming the following reaction:

where x represents the Zircaloy-4 hydrogen absorption ratio. The initial hydrogen content in the Zircaloy-4 specimen was controlled to be below 10 ppm. The corrosion rate decreased with time (90-day values: 2.46×10-3 and 2.37×10-3 μm/y for the gas flow method and 6.72×10-2 μm/y for the batch test). The Zircaloy-4 hydrogen absorption ratio during corrosion was over 90%. The large amount of hydrogen absorbed in Zircaloy-4 will play an important role in the long-term safety for the disposal of irradiated Zircaloy materials.

Type
Articles
Copyright
Copyright © Materials Research Society 2012

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. FEPC and JAEA, Second Progress Report on Research and Development for TRU Waste Disposal in Japan (2007).Google Scholar
2. Hillner, E. et al. ., Long-term Corrosion of Zircaloy Before and After Irradiation, J. Nucl. Mater. 278, 334 (2000).10.1016/S0022-3115(99)00230-5Google Scholar
3. Hansson, C. M., The Corrosion of Zircaloy 2 in Anaerobic Synthetic Cement Pore Solution, SKB TECHNICAL REPORT 8413 (1984).Google Scholar
4. Franker, A. C. and Harris, J. S., Corrosion Behavior of Zirconium Alloy Nuclear Fuel Cladding, Mat. Res. Soc. Symp. Proc. 176, 549 (1990).10.1557/PROC-176-549Google Scholar
5. Kreis, P., Hydrogen Evolution from Corrosion of Iron and Steel in Low/Intermediate Level Waste Repositories, NAGRA NTB 9121 (1991).Google Scholar
6. Wada, R. et al. ., Experimental Study on Hydrogen Gas Generation Rate from Corrosion of Zircaloy and Stainless Steel under Anaerobic Alkaline condition, Proc. Radioactive Waste Management and Environmental Remediation ASME, Nagoya, Japan (1999).Google Scholar
7. Honda, A. et al. ., Japan Patent 2912365 (1999).Google Scholar
8. Yamaguchi, T. et al. ., A Study on Chemical forms and Migration Behavior of Radionuclides in Hull Waste, Proc. Radioactive Waste Management and Environmental Remediation ASME, Nagoya, Japan (1999).Google Scholar