Materials for High-Level Waste Canister/Overpacks in Salt Formations

General Corrosion and Localized Corrosion of the Drip Shield

“…This is clearly borne out by the measured corrosion rates in the absence of radiation which, for Ti Grade 7 are in the range ≤ 100 nm/yr (after ~ 3.5 years of exposure) in Q-brine, and independent of temperature over the range 90 o C to 200 o C (Smailos and Köster 1987). Similarly low corrosion rates (~ 400 nm/yr in a brine containing 35,000 mg/L of Mg 2+ at 250 o C) were obtained for Ti Grade 7 by Molecke et al (1982). The higher rate observed by Molecke et al (1982) can be attributed to the higher temperature and shorter exposure period.…”

“…Similarly low corrosion rates (~ 400 nm/yr in a brine containing 35,000 mg/L of Mg 2+ at 250 o C) were obtained for Ti Grade 7 by Molecke et al (1982). The higher rate observed by Molecke et al (1982) can be attributed to the higher temperature and shorter exposure period.…”

“…This was discussed in the modeling analysis in Section 6.3.4.2. In particular it was shown that even under extremely aggressive chemical exposure conditions (brines containing 35,000 mg/L of Mg 2+ at 250 o C) relatively low rates (~ 400 nm/yr) were obtained for Ti Grade 7 (Molecke et al 1982) and these rates were attributed to the high temperature and shorter exposure period (i.e., higher than the rates based on the long-term parabolic or logarithmic kinetics). It is judged that, since these measured rates are near the upper bound levels of the CDFs, the uncertainties in the corrosion rates due to unanticipated but possible aggressive chemical exposure conditions are included within the CDF distributions.…”

“…These studies range from those primarily interested in the performance of Ti as a body-implant material (Pan et al 1994) to those in which Ti was tested for its durability under nuclear waste disposal conditions (Molecke et al 1982;Smailos and Köster 1987).…”

General Corrosion and Localized Corrosion of the Drip Shield

“…These studies range from those primarily interested in the performance of titanium as a body-implant material (Pan et al 1994 [DIRS 159795]) to those in which titanium was tested for its durability under nuclear waste disposal conditions (Molecke et al 1982 …”