Re: Effect of Sulfate on Pitting?

Posted by Tero Hakkarainen on August 07, 1996 at 05:39:53:

In Reply to: Effect of Sulfate on Pitting? posted by Dr. R.D. Kane on July 28, 1996 at 10:06:08:

: Is it correct to conclude based on your results that
: sulfates in aqueous chloride-containing environments
: do not significantly effect pit initiation or growth?

For pit propagation, yes. The results indicate that once
stable pit growth has been activated by chloride ions,
sulfate ions in the bulk solution, even in amounts very
large compared to the amount of chloride ions, will have
a minor effect only, if any, to the pit growth.

For pit initiation, I have no results. I believe that in
the presence of sulfate ions, significantly higher electrode
potentials may be required to initiate pits than in plain
chloride solutions.

Follow Ups:

Post a Followup

Name:    
E-Mail:  
Subject: 

Comments:
         : : Is it correct to conclude based on your results that
: : sulfates in aqueous chloride-containing environments
: : do not significantly effect pit initiation or growth?

: For pit propagation, yes. The results indicate that once 
: stable pit growth has been activated by chloride ions, 
: sulfate ions in the bulk solution, even in amounts very 
: large compared to the amount of chloride ions, will have 
: a minor effect only, if any, to the pit growth. 

: For pit initiation, I have no results. I believe that in 
: the presence of sulfate ions, significantly higher electrode 
: potentials may be required to initiate pits than in plain 
: chloride solutions.