The passivation behavior of 304L, 316L and 22 %Cr duplex stainless steel has been studied as a
function of mechanical. chemical and/or.electrochemical treatment. Surface energies, impedance spectra
and pitting potentials were evaluated as measures to characterize the functional surface properties.
Specimen blasted with glass beads always performed better than those blasted with alumina. Nitric acid
has no long time benefits as a passivating agent. The influence of citric acid on the passive behavior is
marginal and does in the long run not at all reach that of a air-only passivated specimen.
Keywords: stainless steel, surface properties, passivity