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

<40℃
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