A Microelectrochemical Investigation of Alloy C22 in Chloride Solutions below the Critical Pitting Temperature

This paper describes a brief investigation into the possibility of pit nucleation on Alloy C22 in 5 M LiCI solution at ambient temperature; more than 70°C below the temperatures usually necessary for stable pitting to occur in this material. Short-lived anodic current transients on the order of 10 pC in size were observed to occur at high frequency during short potentiostatic tests. These transients are considered indicative of localized passivity breakdown, showing that the localized corrosion resistance of C22 arises from a high resistance to pit propagation rather than from any special stability of its passive film.

[1]  G. Gordon.  F.N. Speller Award Lecture: Corrosion Considerations Related to Permanent Disposal of High-Level Radioactive Waste , 2002 .

[2]  G. Cragnolino,et al.  Localized Corrosion Susceptibility of Alloy 22 as a Waste Package Container Material , 2002 .

[3]  G. Burstein,et al.  The role of alloyed molybdenum in the inhibition of pitting corrosion in stainless steels , 2001 .

[4]  H. Böhni,et al.  Microelectrochemical studies on the influence of Cr and Mo on nucleation events of pitting corrosion , 2000 .

[5]  R. Newman,et al.  Metastable Pitting and the Critical Pitting Temperature , 1998 .

[6]  R. Newman,et al.  Aggressive effects of pitting “inhibitors” on highly alloyed stainless steels , 1998 .

[7]  R. Newman,et al.  Localised dissolution kinetics, salt films and pitting potentials , 1997 .

[8]  Ricardo M. Souto,et al.  Observations of localised instability of passive titanium in chloride solution , 1995 .

[9]  T. Suter,et al.  Microelectrochemical Investigations of MnS Inclusions , 1995 .

[10]  T. Suter,et al.  Micro- and nanotechniques to study localized corrosion , 1995 .

[11]  Petrus Christiaan Pistorius,et al.  Metastable pitting corrosion of stainless steel and the transition to stability , 1992, Philosophical Transactions of the Royal Society of London. Series A: Physical and Engineering Sciences.

[12]  David E. Williams,et al.  Initiation events for pitting corrosion of stainless steel , 1992 .

[13]  R. Ovarfort.  Critical pitting temperature measurements of stainless steels with an improved electrochemical method , 1989 .

[14]  G. Frankel,et al.  Metastable Pitting of Stainless Steel , 1987 .