|Autors: Loukaycheva, M. H., Tzaneva, B. R., Fachikov L.B.|
Title: Corrosion of high nitrogen stainless steel in sodium orthophosphate solutions
Keywords: corrosion, pitting, high nitrogen steels, incubation time, polarization
Abstract: The corrosion behavior of Cr18Mn12N (0.61% N) and Cr18Ni9 steels in water solutions of sodium orthophosphates (NaH2PO4, Na2HPO4 и Na3PO4) - 0.1 М, with addition of 0.5М NaCl have been investigated by potentiostatic and galvanostatic methods. Galvanostatic results reveal that both steels exhibit almost identical behaviors. The increase in the current density does not affect the value of the stationary potentials reached after 1 hour of polarization. In solutions of NaH2PO4 and Na2HPO4 both steels develop pitting corrosion. In Na3PO4 with added chloride, the steels show passive behavior at the applied current densities; there are indications of pitting occurrence on the Cr-Ni steel surface that subsequently repassivate. The potentiostatic dependencies provide a basis to determine the values of the pitting formation potentials, Еpit and the incubation time of the pitting nucleation. The recorded Epit for the nitrogen steel have more negative values than those obtained with Cr18Ni9 steel.
Вид: статия в списание, публикация в реферирано издание, индексирана в Scopus
Въведена от: доц. д-р Боряна Рангелова Цанева