(1) A spring-shaped shape memory alloy after shape-setting (training) treatment
(2) At room temperature (below the martensitic transformation temperature), applying a load changes the shape.
(3) Shape after sufficient deformation, with the load removed
(4) When heated above the reverse transformation temperature, it begins to return to the memorized shape. (1/3 recovery)
(5) Continue heating. (2/3 recovery)
(6) Continue heating. (Full recovery to the original shape)