Chloride Stress Corrosion Cracking and 316 Stainless Steel
Chloride Stress Corrosion Cracking and 316 Stainless Steel
(OP)
I have been reading into Stress Corrosion Cracking (SCC) caused by chlorides, which I understand can be quite an issue.
Is there anything you can do to 316 stainless steel to make it acceptable for use in a chloride environment, or is it just recomended to avoid 316 stainless steel in this application? Perhaps solution annealing will help put the carbides into solution?
Is there anything you can do to 316 stainless steel to make it acceptable for use in a chloride environment, or is it just recomended to avoid 316 stainless steel in this application? Perhaps solution annealing will help put the carbides into solution?





RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
It has to so with the FCC crystal structure, 10% Ni, and applied stress.
If you keep the stress below about 10ksi (applied + residual) and the temp below 125F then it will not crack.
There is no Cl level low enough to prevent cracking if the temp and stress are high.
Virtually every piece of SS made has residual stress levels that are over 30ksi unless it has been process by special methods.
If SCC is a risk then use a duplex SS. They have significant resistance.
If you really must avoid it then use a ferritic SS. The nickle free BCC alloys will not chloride stress crack.
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Plymouth Tube
RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
Steve Jones
Materials & Corrosion Engineer
http://www.linkedin.com/pub/8/83b/b04
RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
Much depends on whether the source of chloride is external or internal to the pipe. Much also depends on factors which would tend to concentrate chloride i.e. by evaporation. Dissolved oxygen content plays a role in fully immersed services.
RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
However, there are many cases of CSCC failures. These range from kitchen appliances to bridges and buildings.
Cyclic heating is usually the worst situation. You can get concentration of chlorides as well as thermal stresses.
You must first have some corrosion before CSCC can happen, so if you are safe from crevice corrosion you should be safe from CSCC.
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Plymouth Tube
RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
RE: Chloride Stress Corrosion Cracking and 316 Stainless Steel
Then you move to Ni based alloys.
Remember that Incoloys are just high alloy stainless alloys.
And not all high nickel alloy have good resistance.
Just to keep things in perspective, there are environments that will cause stress corrosion cracking in all alloy systems.
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Plymouth Tube