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Salt spray testing of 4140 and acceleration factor

I am interested in studying the effects of humidity on 4140 carbon material. Where can I find the standards for the ASTM B117 test and what is the correlation or acceleration factor?

STEVEN PARISH
Engineer - MARIANNA, FLORIDA, USA
2003

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2003

Steven - All ASTM standards can be purchased on their website at www.astm.org. B117 is a standard practice for the operation of a salt fog chamber. It is not a test method. By ASTM definitions, test methods must have an expected result (pass/fail, etc.). When you read B117, you'll see that in several locations it indicates that there is not direct correlation between the hours in a salt fog chamber and actual service conditions. B117 is best used as a process control tool and not a predictor of actual product corrosion resistance.

There are several other corrosion tests, ASTM G85, etc. that are used on aluminum. You might want to try a web search on the type of aluminum and corrosion testing to see what you get.

Cynthia L. Meade
- Sylvania, Ohio, USA