Bob the plater checking in...You guys got it right, acids have Hydrogen (the
H in PH), the smallest of molecules, small enough to penetrate into the
matrix of metals and rattle around to create fissures. The "treatment" is to
bake the part in an oven just after processing-I recall 350 degrees for an
hour, (like cookies) speeding up the activity of the hydrogen and driving
most of it out of the part. Yeah, there are non acid baths for copper and
nickel, especially electroless nickel, but the chrome flash at the end is
acidic. Worse is acid pickeling most parts see prior to the plating to
activate the metal; no way in the real world that a plater wouldn't put the
part in an acid regardless of what you told him, I'm afraid. And yeah, the
problem is exacerbated buy the temper of the steel- the more structured and
defined the matrix, the more the potential for a problem. I wouldn't worry
much
about non-ferrous metals and mild steel, though. Bob Jepson in Boston
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