Everyone has their method for cleaning cans. I have been researching the difference between "old" cans vs 3D printed cans and how to clean the new sealed, printed cans.
A good overview is from Silencer Shop--this shows which metals can go in an ultrasonic, solvents, etc. It is meant as a reference.

https://www.silencershop.com/b...leaning-a-suppressor

I don't have an answer on how to a clean a sealed 3D suppressor--special cleaning solutions seem to be the answer: Huxwrx suppressor cleaning sauce, CAT 206 titanium cleaning solution, Purple Power, Simple Green, CLR.