Hydrogen Embrittlement - More Info
After additional research and a conversation with Caswell tech support, I have learned that Hydrogen Embrittlement (HE) can be an issue with any of the plating processes. But to put things in perspective, Caswell points out that in their 14 years of business this has not been an issue with any of their customers (I assume by issue they mean failure of components due to HE).
Out of curiosity, I called two local plating shops asking about HE. One shop didn't even know what HE was and said they plate suspension springs all the time and have "had no problems." Another shop specializing in manufacturing customers (they don't do bumpers) said they bake all hardened steel at 375 degrees for 4 hours after plating especially when using an acid pickle (for zinc, they only bead blast - no pickle). By hardened steel they mean anything above Rockwell 30 (C scale I think) and 180,000 tensile strength. As a point of reference, they said a grade 8 bolt would be borderline and should be baked.
I have come to the conclusion that I will not plate critical items made from hardened steel since it is not worth the risk. I'll simply purchase new fasteners. However, I will continue to plate non-critical grade 2 and ungraded fasteners and decorative items as I continue to get EXCELLENT results with my Copy Cad kit.
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