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TIN BRIGHT ACID PLATING
PROCESS-681
This in an acid
tin plating process consist of tin
salt-681 and
two make up, as
well as maintenance addition
agent viz.,carrier
brightner - 684 and brightner - 682. This process
produces mirror
bright deposit over bright nickel or highly buffed brass
surfaces
in rack and
barrel plating processes. This process
is effective
for the
application in the electrical and electronic
industries,
for food processing equipments, kitchen and domestic
tabelware, it
provides a
bright clean, non-tarnishing and corrossion
resistant
finish with excellent solderability.
Bath
make up and operating condition:
Tin
bright salt - 681
30 gm/litre
sulphuric
acid lr grade 105 ml/litre
Tin
brightner - 684
25-30
ml/litre
Tin
brightner - 682 15-20
ml/litre
Density
17-90
Be
Temperature Room
Anode current density 1.0-2.0
Amp/sq.dm
Cathode current density
(rack) 0.5-3.0
Amp/sq.dm
(barrel)
0.5-2.5 Amp/sq.dm
Agitation
Cathode road movement
Filtaration
Occational
Anode
99.99 % pure
Voltage
1-3
(rack),4-7 (barrel)
Rate
of deposition at 2 amp/sq.dm
0.8 micron per minute
Consumption
:
Brightner
682
250-300 ml/1000 amp-hr.
Brightner
684
150-200 ml/1000 amp-hr.
Bath
solution preparation :
1. PVC lined or hdpe plastic tank is properly cleaned with distilled water.
2. Fill
the tank with half the volume of working level.
3. Add
cautiously required quantity of l r grade sulphuric acid with enough stirring.
4. Add
required quantitiy of tin bright salt - 681, slowly with stirring.
5. Dilute
the solution with distilled water to about 90
% of final volume.
6. Allow
the solution to cool to room temprature .
7. Add
with vigorous
stirring, carrier brightner
684, and
mix well.
8. Add
brightner 682 with stirring.
9. Bring
the operating solution to final volume with
distilled water and start plating.
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