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PVD watch case treatment
I AM LOOKING FORWARD TO BUY A WATCH WITH A ROSE GOLD PVD TREATMENT. The case is formed by stainless steel and brass. In your experience how resistant to scratches ,wear etc...are these PVD treatment.I read the 2001 discussion on electroplate v/s goldfilling but I would like a more direct response to my particular case.jose torres
HOBBYIST - SAN JUAN, Puerto Rico
The PVD treatments that are used in (good quality) watch casings are much more resistant to scratching than electroplating. They are also made to much finer tolerances than plating.
An excellent reference is the Longines website. Longines are somewhat unique as they produce premium luxury watches but use exclusively (highly developed) PVD treatments (except for solid and stainless watches of course).
The reason that some manufactures still use electroplating (like TAG Heur) still include mainly the prestige of having a layer of "real gold" on the surface of the watch. What is actually on the top of a PVD watch is a sub-micron finishing layer of gold which highlights the gold colour of the PVD coating (usually titanium nitride). Also, with premium electroplating (20+ microns) scratches can sometimes be very carefully buffed out. As mentioned before, since the top layer on a PVD coating is so thin, if you manage to scratch a PVD coating you can't buff it back.
Hope that some of this may be helpful. Buying a proper watch is fun if sometimes complicated. You need to figure out if you want one for functionality or prestige... or a bit of both.
- Perth, Western Australia
Thanks, Andrew. TiN is certainly a much harder and more wear-resistant material than gold. But the 'finer tolerances than plating' part is a little misleading. Whereas electroplating is a versatile technology that allows 'down and dirty' bulk processing, it also allows super precision deposition. The molds for CDs and DVDs are made via nickel electroplating technology and the highest precision electronics and MEMs are made via copper electroplating technology. Also electroplating is done before PVD processes on most substrates to provide corrosion resistance (although apparently not on Longines watches because the substrate is stainless steel).
It is good to see growth in PVD technology for specific applications where the surface properties offered are a better match to the needs than is available from electroplating, but it isn't a "better" technology :-)
Ted Mooney, P.E. RET
Pine Beach, New Jersey