How to keep aluminum from oxidizing

[Jingle1377]

Hello all, I am tasked with helping with the start up an aluminum tube bending department at an extrusion shop. I am mandrel bending and using a lubricant on the inside of tubes. Afterwards they must be cleaned with a detergent and rinsed to remove lubrication before going through heat treatment process. My expertise lies in years of tube bending and not with cleaning. My problem is how do I stop the aluminum from oxidizing and losing it's luster during this operation? Any an all suggestions will be greatly appreciated. Thanks in advance.

 

[BT Fabrication]

aluminum oxidizes as soon as it hits the open air with oxygen in it, and just gets thicker over time. The processing im guessing you are doing is cleaning the surface and making it a flat sheen from the PH balance of the cleaning soloution. No real way of stopping it, only to polish it afterwards or an acid wash/brightener.

 

[rons]

I use Bonderite on aluminum. There is a cleaning solution and a coating solution.

Bonderite C-IC 33 Aero (Formerly Alumiprep 33) | Aircraft Spruce

Bonderite C-IC 33 Aero (Formerly Alumiprep 33) Use to clean, brighten and transform badly Corroded aluminum to its natural appearance.

www.aircraftspruce.com

Bonderite M-Cr 1001 Aero (Formerly Alodine 1001) | Aircraft Spruce

Bonderite M-Cr 1001 Aero (Formerly Alodine 1001) An invisible coat to provide in-depth corrosion proofing to the brightened aluminum surface and act as a firm barrier against the elements and continued corrosion.

www.aircraftspruce.com

 

[Jingle1377]

aluminum oxidizes as soon as it hits the open air with oxygen in it, and just gets thicker over time. The processing im guessing you are doing is cleaning the surface and making it a flat sheen from the PH balance of the cleaning soloution. No real way of stopping it, only to polish it afterwards or an acid wash/brightener.

Appreciate the info. We are not allowed to polish the tubes as they want it to keep its original look and shine. However we do have an acid wash in the Anodizing department and I do like the sound of that idea, don't know if they'll go for it but's definitely worth a shot. Thanks

 

[Jingle1377]

I use Bonderite on aluminum. There is a cleaning solution and a coating solution.

Bonderite C-IC 33 Aero (Formerly Alumiprep 33) | Aircraft Spruce

Bonderite C-IC 33 Aero (Formerly Alumiprep 33) Use to clean, brighten and transform badly Corroded aluminum to its natural appearance.

www.aircraftspruce.com

Bonderite M-Cr 1001 Aero (Formerly Alodine 1001) | Aircraft Spruce

Bonderite M-Cr 1001 Aero (Formerly Alodine 1001) An invisible coat to provide in-depth corrosion proofing to the brightened aluminum surface and act as a firm barrier against the elements and continued corrosion.

www.aircraftspruce.com

Will the Bonderite coating solution interfere with any welding process?

 

[jim rozen]

"aluminum oxidizes as soon as it hits the open air with oxygen in it, and just gets thicker over time."

It's actually self-passivating. The oxide layer stops at about 10 atomic layers. AFter that it's gas-tight and the oxide growth stops.

His tubing is getting dull because he's using an ALKALINE detergent. That etches aluminum. An acid wash afterwards, won't change a thing.

 

[BT Fabrication]

Will the Bonderite coating solution interfere with any welding process?

I wouldn't suggest it before you weld as there is HF acid as you wouldn't want that vaporizing and breathing it in while welding.

 

[DanielG]

This is a situation for your local Henkel rep. They are the maker of the Bonderite and Loctite products. They make cold forming lubricants and detergents. They should be able to get you a system of chemical system that works well.