Hydrogen embrittlement of duplex stainless steel 2205 and TiPd alloy in a synthetic bentonite pore water

This work is focused on evaluation of the susceptibility of spent nuclear fuel repository canister structural materials to hydrogen embrittlement. The materials studied in these experiments were duplex stainless steel 2205 and titanium alloy with palladium. Both hydrogen absorption kinetics and mechanical properties were studied. Both materials were tested in a solution of sulphuric acid with arsenic trioxide and in the synthetic bentonite pore water. Laboratory temperature, 40 °C and 90 °C and current densities of 0.2, 10 and 100 A.m-2 were used for this work. Some samples were exposed to gamma radiation in an irradiation facility to verify the possibility of hydrogen absorption due to water radiolysis. Hydrogen absorption kinetics were evaluated by means of thermal desorption spectrometry and X-ray diffraction. Mechanical properties were observed by means of a slow strain rate tensile test, U-bend test and impact toughness. Hydrogen absorption in the synthetic bentonite pore water is possible even at lo...