The ability of a material to be heavily manipulated and then return to its original shape. sometimes with the application of heat. Materals with shape memory include synthetic rubbers and certain metal alloys.
A shape memory alloy (SMA, smart metal, memory alloy, muscle wire, smart alloy) is an alloy that "remembers" its original, cold, forged shape, and which returns to that shape after being deformed by applying heat. This material is a lightweight, solid-state alternative to conventional actuators such as hydraulic, pneumatic, and motor-based systems. Shape memory alloys have applications in industries including medical and aerospace.
Shape Memory Polymers (SMP) are polymeric smart materials that have the ability to return from a deformed state (temporary shape) to their original (permanent) shape induced by an external stimulus (trigger), such as temperature change.