According to the Design Binder, it’s a sort of Titanium mixed with Memory Plastic (known also as Memory Shape Polymer).
“Superalloy” is an actual real life thing. It’s a metal that has highly desirable mechanical properties. Real life Superalloys are used in the engines of jet planes, for example. Superalloy also keeps its strength at high temperatures.
Wikipedia has a good article on it. If that’s not your thing, there’s others.