Major problems with aluminum oxidations.

[Sav1]

My company benchmarked a new process about a year ago by blasting mill aluminum with aluminum oxide media to prevent slipping on a major product. The product looks great when it leaves the shop but by the time it reaches to feild for instalation the oxide has sped up the oxidation process and is a solid black color. Which is almost impossibe to get out. We have tried to use a VCI barrier paper with little to no effect. Does anyone have any suggestions? Possibly using a different type of blast media????/

 

[unclesyd]

Comeback with a little more information as the type AL and blast media and conditions

 

[Sav1]

T6061 ALUMINUM, we have what we call a 10200 die that is used as a walking surface board. We blast these perticular boards to reduce slipping and falling when wet. The type of media we use is 90 grit aluminum oxide which we purchase from a local vendor in 400 pound barrels. The conditions in and around the blast cabinet are very dry. When these parts are blasted and ready for packaging they are stacked on top of each other and banded. They are fine while they are in house but 2 months later out in the feild is a different story. The boards start to turn black and almost impossible to remove with any chemicals. We have gone to VCI paper between rows which has helped but has not eliminated the issue. We are spending 10 to 20 thousand extra dollars in the feild to clean or replace. I guess my first question would be what causes this reaction?

 

[israelkk]

I think you should chromic anodize it after blasting otherwise it is not protected against corrosion.

 

[monkeydog]

Sounds like the manner in which it is used is the cause. Foot traffic is transfering contaminates (dirt) and "grinding" it into the material. That is why the tape on strips are helping but not solving the problem. You may want to hard anodize instead of chemical coating.

 

[EdStainless]

You are exposing fresh metal and providing a surface that will trap water and dirt.
A chemical passivation will help.
You might be better off with a scored or scribed surface than blasting. They could drain then.

= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.

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