Effect of zinc injection on the electrochemical behavior and crack growth rate of a 316 L stainless steel in simulated primary coolant of pressurized water reactors

Zinc was added to high-temperature borated and lithiated water and its effect on the oxide film formation, electrochemical behavior and crack growth rate of 316 L stainless steel was investigated. The actual concentrations of zinc in the coolant solution at 300 °C and 350 °C were determined by ICP-Mass spectrometry. Zinc improved the electrochemical corrosion parameters of steel and reduced the crack growth rate of the sample by more than 13 times. Zinc also reduced the thickness of the formed oxide layers on steel and modified the chemical composition of the oxides to a mainly zinc and iron rich spinel.