I use cartridge cases to clean files of debris. I just flatten the mouth of any handy rifle case I have, usually a 30-06 or the like. I don't cut the head off or install a handle,,just use it as-is.
The flattened mouth conforms to the files teeth in a few strokes as others have commented and cleans the junk out of the file in quick order.
I generally have a few of these 'cleaners' lying around the benches so I don't have to go searching for one every time.
A piece of scrap brass 1/2" wide or so and filed to a dull chisel edge will do the same job for you. Put a handle on it if you want to bother to take the time I guess.
Brass works the best. A flattened piece of copper tubeing can do but most being softer than brass, it can leave behind the same type of shards of metal stuck in the teeth like the aluminum you are trying to remove.
Process won't dull the file.
I don't like using a file card,,they never gave me good results anyway regardless of any dulling effect they have on the file.
If your file(s) are dull, send them to a place like Boggs for resharpening. Very inexpensive and first rate results.
...I've got the same set of MillersFalls carving tools. Don't recall where mine came from but they've been with me for a long time. They get a lot of use.