The Long-Term Corrosion Test Facility at Lawrence Livermore National Laboratory

Abstract

The long-term corrosion test facility (LTCTF) at the Lawrence Livermore National Laboratory (LLNL) consisted of 22 vessels that housed more than 7,000 corrosion test specimens from carbon steels to highly corrosion resistant materials such Alloy 22 and Ti Grade 7. The specimens from LTCTF range from standard weight-loss coupons to U-bend specimens for testing susceptibility to environmentally assisted cracking. Each vessel contained approximately 1000 liters of concentrated brines at 60°C or 90°C. The LTCTF started its operations in late 1996. The thousands of specimens from the LTCTF were removed in August-September 2006. The specimens are being catalogued and stored for future characterization. Previously removed specimens (e.g. 1 and 5 years) are also archived for further studies.

Material corrosion issues for nuclear waste disposition in Yucca Mountain

“…A preview of the relative resistance of the five alloys to crevice corrosion during the exposure to the LTCTF has been presented before. 7 However, the characteristics of the passive film that formed on the different alloys for example as a function of the alloy composition, solution pH and testing time have never been studied. It seems apparent that a close examination of the coupons exposed to the LTCTF would provide a first assessment on the persistence of the passive film on these metals in the aggressive LTCTF laboratory environments.…”

“…That is Alloy 825 has the lowest PRE of 32 and Alloy C-22 has the highest PRE of 70. 7 The alloys were exposed to three different aerated brines at 60°C and 90°C. These brines were simulat-…”

Electrochemical Corrosion Testing of Neutron Absorber Materials

“…This specimen was exposed at the water line to simulated cement modified water (SCMW) at 90°C for 2,134 days at the Long Term Corrosion Test Facility (LTCTF), formerly located at LLNL. 13,29 The specimens in the test program were affixed to an insulated and threaded rod through a central hole, as shown in Figure 28. 29 Note that part of the test specimen is cut away in the drawing for clarity.…”

“…13,29 The specimens in the test program were affixed to an insulated and threaded rod through a central hole, as shown in Figure 28. 29 Note that part of the test specimen is cut away in the drawing for clarity. The specimens are held apart by Teflon spacers.…”