Forbrite chrome plating process was designed as a low concentration and ligh throw bath.
It provides a very wide bright plate range.
Ⅰ. Advantages:
1. High current efficiency, 25% is attainable, low energy consumption.
2. Wide bright plate range.
3. Excellent covering power.
4. Addition of sulfuric acid is not required.
Ⅱ. Bath compositions and operating conditions :
Composition | Range | Optimum |
Chromic acid | 190-210 g/l | 200 g/l |
Cr-A 5X | 1- 2 ml/l | 1.6 ml/l |
Cr-B 5X | 2.4-3.6 ml/l | 3.0 ml/l |
Temperature | 30-50℃ | 40℃ |
Current density | 5-12 A/dm2 | 10 A/dm2 |
Ⅲ.
Maintenance
:
For each kilogram new addition of chromic acid, 3ml/l of Cr-B 5X should be added.
In case of spots, yellow or gvey deposits, 0.4ml/l of Cr-A 5X should be
added.