Just aluminum for the baffle structure. I haven't seen any issues with Lawman at all, but I don't really care for Winclean at all.
If you do shoot it /that much/ to wear out the baffle stack, send it back to SilencerCo and they'll toss in a new core and ship it right back. It's not something that will happen overnight by any means. I know very, very few people that have actually shot out barrels---- let alone a can.