|
Effect of contamination in Nickel fluoride Cold Seal bath.
The following bath contaminant limits have been suggested by Qualanod specification.
Contaminants
|
Level not exceeding (ppm)
|
Phosphate ions
|
5
|
Aluminium
|
250
|
Sodium or potassium ions
|
300
|
Ammonium ions
|
1500
|
Sulphate ions
|
4000
|
Seal Quality Tests
|
Acceptance limit
|
Phosphoric acid / chromic acid
(BS 6161 Part 3 – ISO 3210 : 1983)
|
|
Nitric acid pre dip dissolution
(BS 6161 Part 4 – ISO 2932 : 1981)
|
|
Acetic acid / sodium acetate
(BS 6161 Part 4 – ISO 2932 : 1981)
|
|
Acidified sodium sulphite
(BS 6161 Part 4 – ISO 2932 : 1981)
|
|
Dye spot (absorption) test
(BS 6161 Part 5 – ISO 2143 : 1981)
|
|
Admittance test
(BS 6161 Part 6 – ISO 2931 : 1983)
|
- 20 S for 20 m film thickness.
|
|
