Initiation and growth of localized attack in nuclear waste package materials 011
Electrochemical potentiodynamic and potentiostatic polarization experiments were conducted on several candidate nuclear waste package container materials in an acidic brine containing 5 weight percent (wt%) NaCl at various temperatures. Substantial pitting and crevice corrosion was observed in Alloys 825 and G-3 in a 90{degrees}C brine at controlled potentials (E{sub cont}) that were noble compared to the critical pitting potential (E{sub pit}) measured by the potentiodynamic polarization method in a similar environment. The results of potentiostatic polarization experiments performed in a 30{degrees}C brine at E{sub cont} values that were noble compared to the corrosion potential (E{sub corr}) indicate that Alloys 825, G-30, C-4 and 625 suffered from crevice corrosion. Alloy C-22 became susceptible to crevice corrosion at 60{degrees}C under controlled potentials which were sufficiently noble compared to E{sub corr}, suggesting that it had a higher critical crevice corrosion temperature compared to that of the other high-nickel alloys tested. No pitting was observed at 30{degrees}C and 60{degrees}C on any tested materials. But Alloy 625 showed surface cracks in the crevice region. Ti Grade- 12 was immune to localized attach. Tests are ongoing.
- Research Organization:
- Lawrence Livermore National Lab., CA (United States)
- Sponsoring Organization:
- USDOE Office of Civilian Radioactive Waste Management, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 311015
- Report Number(s):
- UCRL-JC--129068; CONF-980520--; ON: DE98058782
- Country of Publication:
- United States
- Language:
- English
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