Cycle chemistry and its effect on materials in a supercritical water-cooled reactor: A synthesis of current understanding

Corrosion Assessment of Candidate Materials for Fuel Cladding in Canadian SCWR

“…Laboratory electrochemical measurements and simulation studies suggest that the large drop in water density and dielectric constant at temperatures well above the critical point leads to a transition from an EO mechanism in the liquid-like phase to a gas-phase CO mechanism. 12,[17][18][19][20] There is a critical SCW density (around 100 kg/m 3 ) above which ion-pair dissociation is high and the EO process is dominant. In the vicinity of this critical density, both the EO and CO processes may occur simultaneously.…”

“…Alloys considered for the fuel cladding must have good mechanical properties and excellent resistance to general corrosion, stress corrosion cracking, and radiation damage. 1,[6][7][8][9][10][11][12] Many studies of the corrosion of materials under simulated SCWR conditions have been carried out since the 1960s. 1,13 There have also been extensive corrosion studies on materials for use in ultrasupercritical coal power plants as well as for supercritical water oxidation systems that are operated under more corrosive SCW chemistry conditions compared to those expected in a SCWR.…”

Analysis of localized oxides and oxide films formed on alloy 625 and 617 in supercritical water and superheated steam environments at 750°C

“…13(c), which is almost single outer layer and its oxide thickness is 0.614 µm. According to the study on the solubility of nonconductive oxide in SCW at 25 MPa up to 600°C, it is reported that the Cr oxide has a higher solubility compared to the Ni oxide (Cook and Guzonas, 2012). Supposing that this tendency remains on to 750°C, the decrease in Cr contents in outer layer on both alloys can be explained to some extent.…”

Generation of Ultrafast Transient Acid Spikes in High-Temperature Water Irradiated With Low Linear Energy Transfer Radiation

“…These products can increase corrosion and degradation rates of reactor components as well as affect the transport and deposition of both corrosion products and radionuclides [4][5][6][7][8], thereby influencing the long-term integrity and performance of reactors. While the radiation-induced chemistry (radiolytic yields or G values and reaction rates) in water at elevated temperatures (say, up to 350°C) is relatively well documented [9][10][11], there are only very limited experimental data available on supercritical water radiolysis [12][13][14][15].…”