Premium
Pitting and crevice corrosion behaviour of high alloy stainless steels in chloride‐fluoride solutions
Author(s) -
Pardo A.,
Merino M. C.,
Otero E.,
López M. D.,
Utrilla M. V.
Publication year - 2000
Publication title -
materials and corrosion
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.487
H-Index - 55
eISSN - 1521-4176
pISSN - 0947-5117
DOI - 10.1002/1521-4176(200012)51:12<850::aid-maco850>3.0.co;2-f
Subject(s) - crevice corrosion , metallurgy , pitting corrosion , chloride , corrosion , alloy , fluoride , materials science , nuclear chemistry , chemistry , inorganic chemistry
The localised corrosion resistance (pitting and crevice corrosion) of two high alloy stainless steels, namely superduplex (SD) and superaustenitic (SA), has been studied in chloride‐fluoride solutions at pH values ranging from 2 to 6.5. The pitting potential (E pit ) and crevice potential (E cre ) have been calculated for these test media using electrochemical techniques (continuous current). The Critical Pitting Temperature (CPT) and Critical Crevice Temperature (CCT) are in both materials lower then the room temperature. In spite of this fact and due to the high repassivation rate, the resistance of these materials to localised corrosion is high in the tested media. At the highest tested concentration of aggressive anions and pH 6.5 both materials undergo a generalised attack.