The birth of corrosion pits as stimulated by slurry erosion

Abstract A novel technique has been developed to examine the details of the slurry erosion–corrosion behaviour of stainless steel in aqueous silica slurry using a modified slurry erosion rig with a two-electrode system. Measurement of current transients of 304L stainless steel in chloride solution shows the propagation of metastable pits immediately after a short duration of erosive particle impingement below the pitting potential. Metastable pit events after the particle impingement are more numerous than those under non-erosive conditions. Erosive impact by solid particles thus stimulates pitting corrosion of stainless steel in chloride solution by nucleation of more metastable pits. It is argued that the effect arises both from exposure of fresh active sites during erosion as well as by altering their geometry.

[1]  G. Burstein,et al.  The generation of surface roughness during slurry erosion-corrosion and its effect on the pitting potential , 1996 .

[2]  B. W. Madsen.  Measurement of erosion-corrosion synergism with a slurry wear test apparatus , 1988 .

[3]  M. Henthorne.  Corrosion of Resulfurized Free-Machining Stainless Steels , 1970 .

[4]  Ian M. Hutchings,et al.  A comparative study of the slurry erosion and free-fall particle erosion of aluminium , 1991 .

[5]  N. Bui,et al.  Electrochemical study of corrosion-abrasion of stainless steels in phosphoric acids , 1988 .

[6]  E. B. Tinker,et al.  Erosion-Corrosion in Slurry Pipelines , 1974 .

[7]  T. Tsuru,et al.  The breakdown and repassivation of passive films on iron whisker and amorphous alloys , 1990 .

[8]  Petrus Christiaan Pistorius,et al.  The nucleation and growth of corrosion pits on stainless steel , 1993 .

[9]  Z. Szklarska‐Śmiałowska.  Influence of Sulfide Inclusions on the Pitting Corrosion of Steels , 1972 .

[10]  G. Wranglén.  Pitting and sulphide inclusions in steel , 1974 .

[11]  U. Bertocci,et al.  An Examination of Current Fluctuations during Pit Initiation in Fe‐Cr Alloys , 1984 .

[12]  W. F. Savage,et al.  The Effect of Test Method and Surface Condition on Pitting Potential of Single and Duplex Phase 304L Stainless Steel , 1979 .

[13]  B. E. Wilde,et al.  Influence of Sulfur on the Corrosion Resistance of Austenitic Stainless Steel , 1967 .

[14]  S. Leigh,et al.  A Statistical Analysis of the Fluctuations of the Passive Current , 1986 .

[15]  G. T. Burstein,et al.  The effects of anions on the behaviour of scratched iron electrodes in aqueous solutions , 1980 .

[16]  Petrus Christiaan Pistorius,et al.  Growth of corrosion pits on stainless steel in chloride solution containing dilute sulphate , 1992 .

[17]  J. Defrancq.  Influence of Surface Treatment on the Pitting Potential of Mild Steel and Pure (Carbonyl) Iron , 1974 .

[18]  P. Pistorius,et al.  Surface Roughness and the Metastable Pitting of Stainless Steel in Chloride Solutions , 1995 .

[19]  Ian M. Hutchings,et al.  Design of a slurry erosion test rig , 1990 .