Fastest Cheapest Way To Remove Gunk

I've got some roller bearing axles with caked on grease -- a lot of them. In the past I've used a brass wire brush and kerosene (on cleaning my SB9A lathe) but these axles seem really thick and stubborn.

My neighbor said to get a steam cleaner; another person said Purple Power. I'm at a loss what to do. A steam cleaner is a big investment which I'd be willing to do unless there's a cheaper easy way.

Thanks