This additive is a greenish liquid suitable for the anodization treatment of Al and Al alloy. The H2SO4 anodizing solution with addition of this the additive is featured with the following merits:
1. Fast film-formation: the maximum film-formation speed may be reaching 1um/min, specially use in thick-film profile production.
2. High productivity: in comparison with the conventional H2SO4 anodizing, solution, the productivity may be increased by 20-40%.
3. Wide temperature range for operation: qualified film may be formed, provided temperature is below 35℃.
4. The oxide film formed by using this additive is featured by its uniformity in thickness and higher hardness, as well as its better coloring effect and sealing result. |
| 1. Bath Composition (For make-up): |
| |
Sulfuric Acid
WN-1 Additive
Al3+
Water |
150±10g/l
20-40g/l
<20g/l
balance |
| 2. Processing Parameters: |
| |
Temperature
Current Density
Agitation
Time |
<35℃
1-3.0A/dm2
While higher current density is applied, agitation of bath solution should be strengthened, to prevent over heat generated.
In accordance with the film thickness requirement, take Tab. 1 shown as below for reference: |
|
Relation between Film-formation Speed and current Density Tab. 1
| Current Density (A/dm2) |
Film-formation Speed (um/min) |
1.3
1.5
2.0
2.5
3.0 |
0.45
0.52
0.65
0.85
1.05 |
|
