抄録
Polarization and Impedance behavior for a scratched specimen of SUS304 were measured in sulfuric acid solution (pH 1.2). The results obtained are as follows.
(1) The size of impedance diagram for the scratched specimen in the vicinity of Flade potential became smaller than that for the non-scratched specimen, but the size for the scratched specimen in passive state became larger than that for the non-scratched specimen.
(2) The rate of change in impedance |Z| with time differed depending on chemical composition of specimen, but it did not change before and after scratching if the same material was used.
(3) It is considered that the change of anodic current density due to scratching represented the non-steady state reaction process immediately after scratching and the change of impedance represented the steady-state reaction process after that.
(4) A computer simulation in the vicinity of Flade potential using an equivalent electric circuit suggested that the charge transfer reaction, disslution reaction and film-formation reaction were markedly activated due to scratching.
