Thermo-mechanical behavior of shape memory alloy spring actuated using novel scanning technique powered by ytterbium doped continuous fiber laser

Abstract

A novel scanning technique for the contactless laser actuation of shape memory alloy spring is presented in this paper. The influence of laser power on the actuation behavior is studied in detail for the power ranges from 5 to 50 W with bias loads of 1.5, 2.5 and 3.5 N. The scanning of the laser beam over the spring increases the temperature of the spring in proportion to the number of scans performed on the spring. With the increase in power, the scanning required for complete actuation decreases. A maximum of 8 passes was required to attain complete actuation for a bias load of 3.5 N at 15 W, whereas only 1 pass is required for actuation against the same bias load above 35 W. A maximum displacement of 28.9 mm was attained for a bias load of 3.5 N at 50 W. The heat generated during the laser interaction and its distribution in the coils of the spring is studied in detail using COMSOL Multiphysics. © 2019 IOP Publishing Ltd.