Bill Putnam wrote:
>My concern is that I know of some parts that have been
>chromed for cosmetic purposes that failed due to hydrogen
>embrittlement. I don't know if this hard-chroming process
>is the same, or if it does not have this problem.
Yes. Hydrogen embrittlement can be a problem with hard-chrome. Embrittlement
is generally a concern when the basis material has a hardness of Rockwell Rc
32 or greater (which is why you need to be careful plating springs).
>Is anyone familiar with this, and ar there steps that can be taken
>while chroming that reduce the likelihood of hydrogen
>embrittlement? This is very important since if this shaft
>did fail it would likely be fatal.
There isn't too much that can be done during plating. The trick is to
conduct a hydrogen bake within a half hour of completion of the plating.
Baking drives off the hydrogen. Time and temperature suggestions available
upon request. Realistically, the bake is something your plater can do and if
they cannot you need a different plater.
FYI, people also go to a fair amount of trouble to specify the finish of the
surface to be plated. Note too that there are limits on the amount of chrome
you can reliably deposit. When the chrome is "turned down" it is usually
ground rather than single point machined. If you stick with an experienced
machine shop and check to make sure you're getting an embrittlement relief
post bake everything should be fine and dothing will grow rong 8-).
just my thoughts. - Bill Ruof
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