Anodizing cannot flake off. It is a penetrating finish. It becomes part of the aluminum. If the frame is left in the anodizing solution long enough you will get a very deep finish. Anodized surfaces are much harder than the non-anodized surfaces. Hard anodizing can be made "file-hard".

So the silver finish is some sort of plating. It should not flake off is properly applied. It is difficult to plate aluminum, however.