Shape memory alloys

Shape memory alloys are made of a mixture of metals, with the specific design that should they be deformed e.g. bent out of shape, they will retake their original shape (at least on macroscopic scale).  A common example of this are shape memory glasses.  In the video below you will see that the glasses easily return to their original shape, When frozen in liquid nitrogen the deformed shape exists until it warms back up to room temperature.

Over time repeated deforming of these alloys will cause them to stop returning to their original shape. Engineering scientists at University of Maryland in the US have developed a new alloys that have the ability to reform their original shape even after being bent 10 million times!  Click on the picture below to read the BBC News article.