Ok - you are telling me that anti-seize compounds like (e.g.) Special 18002 Aluminum Anti-Seize will eat up aluminum?? Great! I use that on my AR upper receivers.
[EDIT] Manufacturer claims you can use on spark plugs for aluminum block engines. (?)
I don't know the composition of that particular formulation. It's that detail that makes the difference.
If you look at the table below, it tells us that the substances at the bottom are the most nobel, meaning they are the things that tend not to corrode, whereas the substances higher up the table are the things that get eaten up when in electrical contact with something lower down on the table and an electrolyte is present. That's why we put zinc sacrificial anodes on saltwater boats, to protect the bronze hardware below the waterline. We put magnesium sacrificial anodes on freshwater to protect aluminum outdrives.
Aluminum is near the top, and carbon (graphite) is at the very bottom. Put them in contact with each other, add an electrolyte like water, and the aluminum gets corroded. On an anodized AR upper or lower, I'm not as worried about graphite because I keep things really dry. As my own rule, however, I don't use graphite when aluminum is involved. In most cases any problems may only be cosmetic, but when clearances are tight, that's another story.
In my situation, the long aluminum monocore slides into the 3/4 inch diameter steel tube. The clearance is very tight and the core is about 10 inches long, which makes for a lot of contact area. I had a devil of a time getting the core out even though I never added any anti-seize. The carbon that really encouraged the corrosion came from the burning powder, as did the moisture (the electrolyte), and no doubt some sulphur or another source of acidity to really make the electrolyte conductive.
I neglected to mention upthread that when I wrestled the monocore out of the tube it looked like an old piece of aluminum that had been left in the bay for a while. Not just the parts of the core in contact with the steel tube, mind you, but all over the entire surface of the core. It was covered in a fine layer of corrosion. I had to get out some very fine sandpaper to knock it off, then grabbed a rag and some polishing compound to shine it up.
While a graphite-based anti-seize may work without problems because the grease it's mixed with will exclude water, in a suppressor I was concerned that the heat and pressures may cook off the grease or blow it out from the tight space between the core and tube such that water could get in there. I decided to skip the whole issue and use a metal-free anti-seize.