Decorative Chrome Plating
Decorative chrome plating is sometimes called nickel-chrome
plating because it always involves electroplating nickel onto
the object before plating the chrome (it sometimes also involves
electroplating copper onto the object before the nickel, too).
The nickel plating provides the smoothness, much of the corrosion
resistance, and most of the reflectivity. The chrome plating
is exceptionally thin, measured in millionths of an inch rather
than in thousandths.
When you look at a decorative chrome plated surface,
such as a chrome plated wheel or truck bumper, most of what
you are seeing is actually the effects of the nickel plating.
The chrome adds a bluish cast (compared to the somewhat yellowish
cast of nickel), protects the nickel against tarnish, minimizes
scratching, and symbiotically contributes to corrosion resistance.
But the point is, without the brilliant leveled nickel undercoating,
you would not have a reflective, decorative surface.
By the way, there is no such thing as "decrotif
chrome plating". That is just a misspelling of 'decorative'.
When an item needs "rechroming", understand
what is really involved: stripping the chrome, stripping the
nickel (and the copper if applicable), then polishing out
all of the scratches and blemishes (they can't be plated over
and any scratches will show after plating), then plating with
copper and "mush buffing" to squash copper into
any tiny pits, then starting the whole process described above.
Unfortunately, simply replating an old piece may
cost several times what a replacement would cost. It's the
old story of labor cost. The new item requires far less prep
work, and an operator or machine can handle dozens of identical
parts at the same time whereas a mix of old parts cannot be
processed simultaneously, but must be processed one item at
a time. If a plater has to spend a whole day on your parts,
don't expect it to cost less than what a plumber or mechanic
would charge you for a day of their time.