Take a closer look @ 'Ultron', the super-villain robot in director Joss Whedon's 3D "Avengers" sequel, "Avengers: Age Of Ultron":
"...with 'S.H.I.E.L.D.' destroyed and the 'Avengers' needing a hiatus from stopping threats, 'Tony Stark' attempts to jumpstart a dormant peacekeeping program with 'Ultron', a self-aware, self-teaching, artificial intelligence.
"However, his plan backfires when Ultron decides that humans are the main enemy and sets out to eradicate them from Earth..."
...before being revealed as 'Ultron-5', the living automaton.
Ultron's outer armor is composed of 'adamantium', an impervious metal composite also used for the skeletal framework of 'Wolverine'.