quantitative stress corrosion cracking analysis

[kclim]

Hello all,

I'm looking for data that may help me establish an SCC propagation rate for carbon steels in nitrate solutions. I understand that there are many parameters to consider, but I'm after some basic figures to get an idea of what I'm looking at.

Also, where can I find a table of K1scc values?

Regards

 

[EdStainless]

I think that the reason that you have no comments is htat you need a stopwatch to measure SCC propigation, not a calender.
IF the condition are present SCC will propigate fast, very fast. In some cases the cracking lowers stresses and it stops, in some cases the corrosant can't get to the crack tip and it stops. In some cases I have seen parts crumble with multiple through wall cracks.
The issue with SCC is initiation, once it starts you are done.

= = = = = = = = = = = = = = = = = = = =
Corrosion never sleeps, but it can be managed.

http://www.trenttube.com/Trent/tech_form.htm

 

[metengr]

kclim;
You might find this paper to be interesting regarding IGA and SCC of carbon and low alloy steels exposed to sodium nitrate concentrations in HRSG (heat recovery steam generator)tubing;

http://home.planet.nl/~whuijbregts/publications/nitratescc/nitratescc5.htm

 

[kclim]

Thanks for your replies

EdStainless - I got the impression that these cracks propagate quite rapidly too - once a critical crack size is reached. Is there any data on how long the cracks take to initiate?

metengr - I've seen the paper related to your link, it was actually one of the first pieces of literature I came across since I was first asked to undertake this investigation. It's quite a good paper.

 

[metengr]

kclim;
There are many variables that effect SCC initiation and propagation. If you need specific corrosion data, most likely you will need to use a technical resource like ASM Metal Handbooks, a Corrosion Handbook or NACE Documents. I have a number of technical sources, and I could not find any specific KIscc data or SCC propagation data for exposure to nitrate solutions.

If you graduated or attended a local University or College, their library may have this information. I have had to contact the University I attended on several occasions for resource material.