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There you go again, putting words into my mouth. Where did I say that embrittlement is a major factor in ALL stress corrosion, AND that it is limited to slow activity at high temperatures?
One paper on stress corrosion is here;
http://www.npl.co.uk/upload/pdf/stress.pdf
This includes embrittlement as a factor. It includes time/temperature graphs showing time involved for stress corrosion to occur.
I do not doubt the PM poster's statement that the springs failed, nor did I say that I did. What has no validity is to infer that stress corrosion is the result of his application. What no one knows is the condition of the springs prior to use of the ER. Corrosion of the calipers and springs did exist prior, otherwise why the need to immerse in ER. The extent is not known, nor is it known what the actual cause of the failure is. It can be somewhat safe to assume it was due to corrosion of some sort. Whether plain corrosion or stress corrosion is immaterial as it had more than likely occurred prior to immersion. Since the degree or type of corrosion prior to immersion is unknown/unproven, absolutely no assumptions can be made as to whether ER contributed to further corrosion or not.
The PM poster did not conduct an experiment. He made no observation as to the cause of the failure. The only person making an assumption as to the cause is yourself. If a proper experiment is to be conducted, it would be along the lines of immersing known good samples of spring steel in ER over timed periods and observing the results. Perhaps at some point, SC will occur, but I doubt it would not be until long after anything approximating normal use would entail.
The Evaporust rep did not pivot away from the issue. His statement is "Evapo-Rust will not harm spring steel." That seems pretty unambiguous to me.
One paper on stress corrosion is here;
http://www.npl.co.uk/upload/pdf/stress.pdf
This includes embrittlement as a factor. It includes time/temperature graphs showing time involved for stress corrosion to occur.
I do not doubt the PM poster's statement that the springs failed, nor did I say that I did. What has no validity is to infer that stress corrosion is the result of his application. What no one knows is the condition of the springs prior to use of the ER. Corrosion of the calipers and springs did exist prior, otherwise why the need to immerse in ER. The extent is not known, nor is it known what the actual cause of the failure is. It can be somewhat safe to assume it was due to corrosion of some sort. Whether plain corrosion or stress corrosion is immaterial as it had more than likely occurred prior to immersion. Since the degree or type of corrosion prior to immersion is unknown/unproven, absolutely no assumptions can be made as to whether ER contributed to further corrosion or not.
The PM poster did not conduct an experiment. He made no observation as to the cause of the failure. The only person making an assumption as to the cause is yourself. If a proper experiment is to be conducted, it would be along the lines of immersing known good samples of spring steel in ER over timed periods and observing the results. Perhaps at some point, SC will occur, but I doubt it would not be until long after anything approximating normal use would entail.
The Evaporust rep did not pivot away from the issue. His statement is "Evapo-Rust will not harm spring steel." That seems pretty unambiguous to me.
JR
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