What is Hydrogen embrittlement in fasteners?
How can you test presence of Hydrogen?

Answer Posted / anil kamat

During plating of cast iron fasteners , when the fasteners
are dipped in the Acid tank , metal reacts with acid thus
lierating free hydrogen which then is absorbed by surface
of metal forming hydrates.
To remove these entrapped hyrogen , process of
deembritlement is adopted which is by baking
the fasteners at about 200 degrees and holding for some
timeat that temperature and gradual cooling.

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