**Author details**

48 Smart Actuation and Sensing Systems – Recent Advances and Future Challenges

**Figure 19.** DSC scans before laser machining and in correspondence of each fabrication process.

**Figure 20.** SEM image of a micro-snake NiTi sample obtained starting from a 120μm NiTi sheet.

Strain-recovery and thermo-mechanical cycling tests demonstrate the high performance of this micro-snake sample. As an example, under the constant load of 16mN, it reaches about 40% of recovery with a cycling stabilization within few hundreds of cycles, when heated by electrical current (130mA) with a maximum power consumption of 0.3W and a frequency of 0.15Hz.

In this work, new developments on SMA actuators in the mini/micro scale are presented: the attention was focused on straight NiTi thin wires and mini/micro snake-like NiTi samples.

Several working parameters have proved to strongly affect the functional and fatigue properties of SMA actuator, such as the electrical pulse performed to heat a wire, the

treated at 400°C for 15 minutes and quenched in water.

**4. Conclusions** 

The fabrication process previously described can be used to produce snake SMA sample of different length. As an example, Figure 20 depicts the SEM image of a micro-snake NiTi sample with 19 curvatures (i.e. 3.8mm of length) obtained starting from a 120μm NiTi sheet Adelaide Nespoli\* , Carlo Alberto Biffi, Riccardo Casati, Francesca Passaretti, Ausonio Tuissi and Elena Villa *Consiglio Nazionale delle Ricerche, Istituto per l'Energetica e le Interfasi (CNR-IENI), Lecco, Italy* 
