[Wish]

there is not. those words are just pointing out that forged armors won't be destroyed.

"broken armor" is more like a triggered state, similar to being diseased, lucky, having an air shield, etc.

it will show up as an icon, and will only go away once you station the unit in a city with enough resources to accomplish it. (I'm actually not sure if this works.)

So, in effect, your unit can have "broken armor" whether or not they are wearing a suit of magic armor, but, the magic armor will not be lost from their inventory.

there is no enchantment to my knowledge that will protect from this...

however when a spell can be "negated" it is usually through magic resistance.