I refinish severely corroded aluminum rims. I use a wire brush to remove the flaked clear coat, wash them , use an oscillating tool to sand the rims with progressively finer grades of sandpaper, polish them , and spray them with clear coat. I used one container of Mothers polish, a package of sanding disks for the oscillating tool, and one can of clear coat to do the job.
How to use an oscillating tool : https://www.youtube.com/watch?v=nJtzpTvwDV4
Four years ago I painted a set of rims with rust paint - they still look good and haven't needed repainting after 3 Canadian winters :
https://www.youtube.com/watch?v=eaBsHrAJnpw