What would you use for this? My one attempt many years ago, trying to use tin/lead solder on aluminum wire was a bust. It looked like water bouncing off a hot teflon frying pan
I want to say I saw a product years ago that could be soldered to aluminum, but it's been too long to recall any details.
If you can patch a radiator using that, I say go for it. The sad thing is that radiators have evolved into almost un-repairable items
(Spellcheck prefers irreparable, and doesn't like un-repairable , but I do