Basically, whenever something cold meets a metal, the metal becomes more brittle by the second. Liquid Nitrogen has the ability to nearly flash freeze anything it touches, solid or gas. Whenever LN2 touches a solid, the solid becomes brittle and breaks quite easily. So, whenever LN2 touches a metal in the game and you put air over the affected area, the are should break. 

@cxi (View Post)

 True, it would break saves. Can't really say much since older ideas for changing elements have broken saves, but it doesn't make it right. I just find doing this would make things more interesting for new saves.