This paper was investigated the effects of nitrate, sulphate and bicarbonate ions, NO
3-, SO
42- and HCO
3-, which are components of the tap water, on occurrence and repassivation for creviced corrosion of flat healds, 13Cr stainless steel components used for a water jet loom(WJL), in 0.11-5.6 mM chloride ion, Cl
-, solution when the electrode potential of test piece was kept at 570 mV vs. SHE.
An occurrence of creviced corrosion in Cl
- solution was inhibited by presence of more than an equimolar amount of NO
3- to Cl
-, or in excess of an equimolar amount of SO
42- to Cl
-. A growth creviced corrosion in Cl
- solution was passivated by presence of more than an equimolar amount of NO
3- to Cl
-, or more than six molar amount of SO
42- to Cl
-. The term required to repassivate crevice corrosion completely after NO
3-or SO
42- was added to Cl
- solution decreased with increasing NO
3- or SO
42- concentration. HCO
3- did not inhibit an occurrence of creviced corrosion and not repassivate a growth creviced corrosion for flat healds in Cl
- solution. This is because that HCO
3- exists in H
2CO
3 as non-dissociation form in the pH 2.2 acidic solution in corroding crevice on test piece, due to dissociation equilibrium. A growth creviced corrosion on test piece was repassivated in Cl
- solution, as a result of the addition of NO
3-, SO
42-. This results that corrosion current decreases with increasing pH
C.C., and then the pH of solution inner the crevice corrosion, the pH
C.C., exceeds depassivation pH, pH
d, irrespective of the type of anion.
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