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Alum oxide impregnated abrasive mats deoxide aluminum?

Today I successfully completed a knowledge and practical class on chemical conversion for aviation application. In some of the training materials it suggests that "abrasive mats (Non-woven Non-metallic) impregnated with aluminum oxide, used to deoxide the metal..." in the section containing tools for surface preparation. Since it has been a while since high school chemistry, I re-visited the periodic table and refamiliarized myself with aluminum and chromium.

My question: Would you believe this a misprint, as a misinterpretation of the source, or how does aluminum oxide expunge oxidation from an aluminum surface, necessary to achieve the water break free test?

Ben Hathaway
aviation - Lakeside, California, USA
2005

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I may be misreading, Ben, but it sounds to me like they're talking about sandpaper, not chemical reactions.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2005

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First of two simultaneous responses --

Non-woven, non-metallic aluminium oxide impregnated abrasive pads is the actual description of (sorry about using branding here, a bit like saying Hoover for vacuum cleaner) a Scotchbrite Pad. We all know how effective they are at abrading surfaces. The grade of aluminium oxide impregnated into the fabric determines the abrasiveness.

Brian Terry
Aerospace - Yeovil, Somerset, UK
2005

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Second of two simultaneous responses --

Ted is correct. This a mechanical application using like materials. Meaning, you are basically using an alum. fiber wheel or belt to work an alum surface.

AF Kenton
retired business owner - Hatboro, Pennsylvania
2005

Thanks for your help, guys, in response to my question about alum. oxide abrasives. Coincidentally, I came across the same description for a brand of sandpaper. I was hoping for a more theoretical explanation of how an alum. oxide product bonds to remove alum. oxidation. Guess I may have been overthinking this one.

Ben Hathaway
- Lakeside, California, USA
2005

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Aluminium oxide, when treated, can become a very hard material (Mohs scale +9, diamond is 10). Which can be used for abrasive purposes.

Basically, you are scratching off the things on the surface of the material you are polishing.

Do correct me if I'm wrong.

Yong Tze Shoong
- Johor, Malaysia
2005