i have read that stainless steel barrels are subject to the crowns being damaged but was wondering if Chrome lined Ar15 barrels crown can also be damaged as well from like aluminum clreaning rods.

The crown on any barrel can be damaged, whether stainless or otherwise.

Clean from the chamber end.

I always do but my rod as it pokes out the end usually makes contact with the crown as it leaves the barrel. I think someone told me the chrome lining is so hard, it could not scratch the barrel if it is an aluminum rod.

If you're that concerned about it, ditch the rod and use a boresnake.

__________________
-John

You can also get a coated cleaning rod.

Which would be better than a threaded section aluminum rod or dirty bore snake.

A coated bore rod with a bore guide that fits in the chamber. Brass jags and brass bore brushes. Some folks use nylon brushes.
After using the brass brush, squirt a little brake cleaner or alcohol on the brush to stop your copper solvent from eating the brush.
Some folks don't use ammonia-based solvents on chrome-lined bores because they believe it can eventually cause the chrome to flake off.
The brass jags and brass or nylon brushes are not going to hurt your crown.
And push the brush or jag w/ patch all the way thru the barrel before reversing it.
Sorry if you know some of this already, but Not sure that you do.

Aluminum rods have a tendency to get embedded with the **** in your bbl. Not good.
I only use bore snakes on .22s, but they can be cleaned, from what i understand.