CYCLING OF A THERMAL ACTUATOR MADE OF NITI ALLOY MANUFACTURED BY SELECTIVE LASER MELTING

This article presents the results of a study on the shape recovery characteristics of a thermal actuator with complex geometry during cyclic actuation. The actuator was fabricated from a nickel-titanium shape memory alloy (Nitinol) using selective laser melting. Cyclic testing was conducted over 20 cycles at a strain of 25.53%. The phenomenon of shape memory effect stabilization during cycling was observed. The shape recovery ratio of the thermal actuator was determined throughout the cycling process. It was found that the shape recovery ratio stabilized at 99% or higher between cycles 9 and 20, with a maximum value of 99.59% achieved at cycle 17.
The accumulated irreversible strain after cycling was determined to be 10.46%. The minimum irreversible strain per cycle was 0.10% at cycle 17. The study confirms the functionality and effectiveness of the selected thermal actuator geometry, demonstrating the promise for further research and development in this area.