1. FEATURES
Environmentally friendly blue passivation without hexavalent chromium, suitable for rack and barrel plating.
A dense blue passivation layer can be formed on the zinc nickel alloy coating, which has strong anti-corrosion ability.
The passivation solution has a long service life and is easy to operate and maintain.
2. PROCESS FLOW
Zinc nickel alloy plating → Rinsing → Antioxidant film removal → Rinsing → Immersion in TR-391 → Rinse →Sealing → Dry
3. OPERATION CONDITIONS
Operation Conditions | Optimal | Operating Range |
TR-391A | 25ml/l | 20-30ml/l |
TR-391B | 50ml/l | 40-60ml/l |
pH Value | 4.5 | 4.0-4.8 |
Passivation Time |
Rack plating 45s Barrel plating 30s |
Rack plating 35-55s Barrel plating 25-35s |
Passivation Temperature | 25℃ | 25-40℃ |
Note: Before passivation, diluted hydrochloric acid with a pH value of 2-3 is required for antioxidant film removal treatment.