A stress corrosion cracking mechanism based on surface mobility

The interaction of strain-rate and repassivation rate in stress corrosion crack propagation

Anodic rate-controlling steps in transgranular stress corrosion cracking of α-brass in NaNO2 solutions

Stress corrosion cracking of stainless steels in high temperature caustic solutions

Stress corrosion cracking, or environmentally induced cracking, is a challenging subject for very many reasons. It stands as an equal challenge to physicists, chemists, electrochemists, metallurgists, mechanical engineers, etc. It has been suffered by the human race since as long ago as the Bronze Age, but no convincing explanation has been found so far for this phenomenon. Many theories have been suggested, but, in spite of the optimistic claims of their authors, among which the present writer is included, Nature has inevitably condemned them to a poor, short life.

Electrochemical Aspects of Stress Corrosion Cracking

The straining electrode technique was used to evaluate the stress corrosion cracking (SCC) susceptibility of AISI 304 stainless steel in 20N NaOH solution, and of Inconel 600 Alloy and Incoloy 800 Alloy in boiling 17.5N NaOH solution. The crack propagation rate estimated from the straining experiments correlated well with failure time measurements from previous constant load experiments. It was found that the straining electrode technique is a useful method for estimating, through short term experiments, parameters like crack propagation rate, crack morphology, and repassivation rate, as a function of the electrode potential.

Stress Corrosion Cracking and Anodic Behavior of AISI 304 Stainless Steel, Inconel 600, and Incoloy 800 Straining in Boiling NaOH Solutions

The effect of various oxyanions in inhibiting the stress corrosion cracking (SCC) of Type 304 stainless steel in boiling 20N NaOH has been investigated. Times to failure of wire specimens were measured in the absence and in the presence of various oxyanions in the NaOH solution. Out of 16 oxyanions tested, CrO4= was found to be the most effective in inhibiting the SCC of Type 304. The CrO4= ions in the caustic solution form a redox couple which shifts the corrosion potential of Type 304 into its passive region where the SCC susceptibility of the alloy is least. The threshold concentration of CrO4= in 20N NaOH is 0.005M. No harmful effect of CrO4= ions on Type 304 was found in this study in the 5 concentrations from 0.001 M to 0.92M investigated.

Y. S. Park

Papers

Stress Corrosion Cracking and Anodic Behavior of AISI 304 Stainless Steel, Inconel 600, and Incoloy 800 Straining in Boiling NaOH Solutions

Inhibitive effect of oxyanions on the stress corrosion cracking of Type 304 stainless steel in boiling 20N NaOH solution