Topic: no cyanide silver plating over copper
Hi,
I'm an artist, so I don't have silver plating background. I would like to start silver plating at home. I need to silver plate, copper plates, which are polished. After silver plating I need to polish the surface to get a mirror like silver.
I want to use silver bath which is not contains cyanide. I was searching on the internet and I found 2 possible bath solutions:
1.)
Silver chloride 30-50g/l
Sodium thiosulphate 500g/l
Sodium metabisulphate 30g/l
for pH: sodium bisulphate
0,5A/dm2
2.)
AgCl
KI
temperature: 30C
I couldn't find much informations about the second one, except the silver will be a little bit yellow, but no adhesion problem. Do you know anything else about this? How much (g) from AgCl and KI I need to use in the bath? Any experience with this?
The problem is with the first one is the poor adhesion. How to solve this problem?
Ammonium thiocyanate? In other forums I didn't get clear answer about safety and adhesion questions, so maybe not.
Then I found, that I can use nickel plating first as a pretreatment. I was keep reading about nickel plating pretreatments and I saw, I still will get poor adhesion just with nickel. I saw it somewhere, that after nickel plating, I need to use copper strike for good adhesion and then silver plating.
But why I can't use copper strike just simply on the copper plate, so don't need to nickel plate???
Do you have any other ideals as a pretreatment?
What can be the process?: polish the copper-clean it- washing-nickel plating- washing- copper plating-washing- silver plating? OR polish copper-clean-washing-copper plating/strike-washing-silver plating? Can be good as well? Can you offer any NO cyanide copper strike solution?
Last edited by daginhun (01/12/2013 - 08:44 AM)