I know nothing about the properties of the various bike frame metals.
That said, on my 2004 Bianchi Axis - on the underside of the downtube - I've got some paint bubbling and flaking off around the threaded holes, revealing what I assume is the bare aluminum? (Please correct this if I'm wrong). I've attached an image.
Is this bad? If so, is there anything I can/should do to treat it?
I appreciate any advice.