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  for Metal Finishing since 1989
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I have problem for anodizing process

2007

Our product had used material A6061 and our process follow : Forging --> Lathe --> Wet Barreling mirror --> annealing 500°C-150 minutes and cooling by water --> anodizing.
But we had got the bad result about the surface of parts had uneven shiny (some area shiny some area blur).
And I had try to used the vacuum annealing with 500°C-40 minutes and continuous process to complete anodizing. We can get the good result, it's not happen for uneven shiny defect.
But for the situation of our company the method will impossible.
Whom can teach me how to solve it and the root cause of this defect.
Thank a lot for your help.

Trung Nguyen Tan
Consumer - HoChiMinh city, Vietnam

We had the same problem before but now we get the answer. This is caused by the two processes: annealing and quenching. Some alumina is produced on the surface of the product in these processes. So you should polish the surface of the product before anodizing.

Richard Ku
- Taicang City, Jiangsu Province, China
2007

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2007

HI
If the anodizing surface is shiny is under etching time. Check your etching time (depend on Alkaline etching Sodium Hydroxide or Acid Etching Sulfuric Acid)
Good Luck

Dai Nguyen
- San Jose, California, USA