EVALUATING THE SENSITIVITIES OF AISCC SUSCEPTIBILITY IN STAINLESS-STEEL NUCLEAR WASTE STORAGE CANISTERS FOR DEVELOPMENT OF A LIFETIME PREDICTION MODEL

Spent nuclear fuel (SNF) is currently stored across the US in passively cooled stainless steel dry storage canisters (DSC). Due to the design of the DSC, aerosols from the outside environment are able to deposit on the stainless-steel canisters. Over time the deposited aerosols will deliquesce on canisters to form concentrated salt brines resulting in localized corrosion, which when coupled with the high residual stress around welds can lead to stress corrosion cracking (SCC). The scope of the work presented is to investigate the boundaries of SCC to varying sensitivities such as environmental factors, microstructure variability, and material composition. These sensitivities will allow for recommendations to be made for canister monitoring and which variables are of the greatest concern for SCC of the DSCs. The data generated will be used in probabilistic FM predictions of AISCC growth for lifetime management of DSC. These predictions will inform a framework to quantify and manage a risk-based ranking of storage sites.
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