Sound technical content, curated with aloha by
Ted Mooney, P.E. RET
Pine Beach, NJ
The authoritative public forum
for Metal Finishing since 1989
-----
Dots on the surface after black anodizing
Hi,I am Patrick and I am an industrial engineer in China. Now I got some aluminum samples (5052-H32) from our supplier. The problem is that there are about 15% samples have many almost evenly distributed hollow dots on the surface after black anodizing (I do not know the detail anodizing process) .I'd like to know what is the reason of this problem.Thank you for your help.
Patrick ZhaoIndustrial Engineer - China
2006
First of two simultaneous responses -- 2006
Patrick,
There can be lots of reasons. Altho the 5052 code would indicate a wrought alloy, if it were really a cast or extruded aluminum, the problem could be in the metal. Since it is a high copper and other metals alloy, it might have been in an acid tank too long. It could be that they were stripped and re-anodized.
Without the traveler(assuming it is correct) and the actual parts, it is nearly impossible to say what the precise cause is.
- Navarre, Florida
Second of two simultaneous responses --
A picture would help a lot here. It sounds like the parts could have been anodized in a chloride-contaminated bath. But this is just one, of many possibilities.
Marc Green
anodizer - Boise, Idaho
2006
2006
emmm..
Any simple way to eliminate the chloride contained inside the anodizing bath?
Thanks
- Malaysia
Q, A, or Comment on THIS thread -or- Start a NEW Thread