Effect of Beam Shaping in Fast Laser Shape Setting on Functional Performances of Thin NiTi Shape Memory Alloys

In recent years, the use of laser technology has been demonstrated a successful and advanced method for fixing the functional performances of thin NiTi Shape Memory Alloy wires. The extremely fast heating and cooling of the wires promotes significant differences in the material performances with respect to standard wires, which are furnace treated.

However, the thermal cycle can be largely tuned by the adjustment of the spatial configuration of laser power density, i.e. laser beam shaping. In this work, the effect of laser beam shaping on the functional performances of thin NiTi wires was explored. Differential scanning calorimetry and strain recovery testing were carried out for the determination of the transformation temperatures and the recoverable strain upon thermal cycling. These results were compared to the ones of the commercially available wires.