Normally the steel wallet will not be affected by the X-ray machines, it is an electronic storage device or a a kind of mini PC....
BUT : If you are unlucky and seen in the company of a suspected Terrorist or Kiddiefiddler who you met maybe on the flight and had a friendly conversation with.....THEN maybe the airport security will ask you to provide access to your steel wallet, just to make sure there are no naughty pics on it or terror plans.......
In some countries you can decline to provide the password but then will get locked up until you change your mind... all up to you
