Answer / 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.

Answer / vimal.v.p

The brittleness induced as a result of Diffusion of Hydrogen
atoms into metallic lattice is known as Hydrogen embrittlement.

This happens in Fasteners during the wire
preparation stage when the raw wire is in contact with HCl
in derusting tanks. When Metal react with Acid , Hydrogen
is liberated , which will be absorbed by metallic surfaces.

Also This phenomenon is sound during electroplating
of high grade fasteners, which will be rectified by baking
the fasteners at about 200 degrees and holding for some time

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