|
|
|
 |
I want to plate copper jewelry with gold color via p.v.d. coating processMay 7, 2009 I want to plate gold on copper finish jewelry with high durability of gold plating with lower cost than real gold direct forming by rectifier . Agrawal Abhishek
May 15, 2009 Firstly, PVD is more expensive than conventional electroplating becuase you need a high capital expenditure on a vacuum system and chamber. Assuming you have access to a PVD system you need to deposit a thin layer of TiN (titanium nitride) - this will give you your gold colour. However, it may not be the right colour for you, so you can then plate the TiN with a thin layer of gold. If your TiN is too thick, you will have problems depositing the gold, becqause TiN is rather non conducting. The trick to it is to use the substrate's conductivity to deposit a thin layer of gold over the TiN, using discontinuities in the TiN layer to allow the current to pass through the TiN. You will get increased wear resistance this way, because the gold will be deposited over a rough TiN surface and it will fill in the "valleys" in the TiN. The gold on the "peaks" will wear away to expose the much harder TiN and this will then protect the gold still left in the valleys.
May 18, 2009 Actually, TiN is a very good electrical conductor. As noted, you may have to add a gold layer on top to get the exact color that you want. Another way is to deposit an alloy nitride, mixing the titanium with zirconium. ZrN is more of a champagne gold. Addition of a little carbon to either will darker the hue. You have to be careful with the carbon, though -- too much and you get magenta.
June 1, 2009 A layer of gold on TiN is generally deposited on watch straps,
cases etc in the same chamber by PVD. However depositing gold by PVD
requires huge investment in gold and recovery of unused gold is
difficult. It would be ideal if gold can be electroplated on TiN. But
it appears to be difficult. H.R. Prabhakara
 |
|
Save
This Page (why?) - Home - ©1995-2009 finishing.com
52068
