Laser Assisted Shape Setting of Superelastic NiTi Wires

A non-conventional method for NiTi wire shape setting using laser beam is experimented. On cold drawn wire  (dia. 100 mm) a single laser scanning pass induces superelasticity to the NiTi wire. Laser scanning rate of the order of 50 mm s^-1 was applied. The performances of the laser annealed wires are evaluated through differential scanning calorimetry and tensile loading/unloading tests and compared to the ones of commercially available materials of same diameter. It is found that the fast laser heat treatment confers improved functional performances (lower thermal hysteresis and extended stress induced martensite plateau) respect to those of commercially available furnace annealed superelastic wires.