IMPEDANCE MEASUREMENTS ON UO2+X IN SATURATED NACL SOLUTIONS

The corrosion on UO2 in sat. NaCl solution was studied by use of imped ance measurements. Within a potential range up to + 600 mV (SHE) a UO3 -surface layer is built up. At higher anodic potentials this surface l ayer is totally dissolved due to corrosion. At rest potential the corr osion rates are dominated by the solubility of the surface layer. From experiments it can be seen that at pH values smaller than pH 5 the co rrosion rate increases linearly with decreasing pH. At pH-values highe r than pH 5 a surface layer is always present and grows with time.