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Sealing of mirror luster, bare aluminum surfaces reaching 500F

Q. Protection of bare aluminum surfaces polished and buffed to a mirror luster extreme:

Whether performed by an aluminum polishing shop or on a D-I-Y basis, bare aluminum surfaces polished to a mirror luster extreme are obviously highly susceptible to the dulling effects of oxidation. For parts not having elevated operating temperatures, frequent application and re-application (every 30-60 days) of grit-free Carnauba waxes function quite well to prevent oxidation from getting a toehold at onset. However, I have not been able to identify an acceptable sealer for parts whose operating temperatures may reach 500°F.

There are sealers for commercial truck wheels. These wheels may periodically reach extremely high temperatures due to thermal conduction of brake heat. These sealers are quite effective for about six months in non-coastal areas. However, these high-temp sealers highly degrade the level of shine of mirror luster finishes.

I am attempting to locate a material that will seal these high-temp (500 °F) surfaces without degrading the mirror luster. Having to frequently reapply the material is not objectionable. In this case, clear coats are out of the question.

Thanks,

Lynn M. Perry, Sr.
- Plano, Texas
2002