Advanced gas-cooled reactor (AGR) oxide fuels used in the United Kingdom are clad bespoke grade 20%Cr-25%Ni-Nb austenitic stainless steel. Electrochemistry was first applied to correlate breakdown potential with chloride ion concentration, temperature, and pH for this alloy. At near-neutral unsensitized material exhibited a linear Eb = A + B log10[Cl−] relationship, where 0.7 VSCE –0.098 V/deca...