According to the company that refurbished two sets of wheels (one steel, one alloy) it is better not to shot blast alloy wheels to remove the paint, as it can damage the soft alloy.
Better to use chemicals for that, after which the alloy is shot blasted with low pressure to prepare the surface for further coating.
Steel of course can be shot blasted.
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<font color="blue"><i>1980 TR7 DHC (my first car, currently being restored)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
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