Reducing SCC on 316/316LSS 1

[Tuckabag]

Are there any treatments/coatings available that will help reduce SCC in 316/316LSS material?
I know we can use exotics such as Duplex, however some of the tube fittings/tube required are either not available in these materials or have ridiculous lead times.
I was considering one of the corrosion inhibiting coatings that Silcotek provide, however they have advised that they do not assist in prevention/reduction of SCC.

Thanks.

 

[EdStainless]

If you suppress all active corrosion then you can prevent SCC.
So in practical terms if you have an application where SCC is "very probable" you can do everything possible and maybe reduce it to just "highly likely".
Move to an alloy that offers resistance to SCC.

For every problem there is a solution that is fast, cheap, and wrong.

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P.E. Metallurgy, Plymouth Tube

 

Chloride ion SCC is the Achille's heel of austenitic stainless steels.
To eliminate it you need to remove at least one of the three conditions necessary for cracking:
1) Vulnerable material
2) Corrosive environment (temperature, chlorides)
3) Tensile stress (including residual)
You can never really eliminate 3), and chloride ions are probably unavoidable because the environment is a given. Chloride ion concentration can be as little as a few ppm.
As far as reduction/mitigation goes, all you can do is fully anneal the steel. But basically you don't ever want to use austenitic SS in a warm aqueous chloride environment.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

 

[EdStainless]

That said, 304/316 are commonly used in mild chloride environments in the 150-250F temp range without cracking.
Annealing alone rarely helps, since rapid cooling from anneal results in high residual stresses.
If the alloy is immune to corrosion you won't have SCC.
You need to understand the entire corrosion situation.
I have seen people have SCC issues, so they move to an alloy with better SCC but no better pitting resistance. And they end up with pitting failures.

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P.E. Metallurgy, Plymouth Tube

 

[Tuckabag]

Thanks for the responses all.
Reinforced what I thought already that there ins't any real viable option apart from exotics.
I will continue down that path.
Cheers.