Using Magneto-Optical Measurements for the Evaluation of a Hybrid Magnetic Shape Memory (MSM)-Based Microactuator

Magnetic shape memory (MSM) materials present a new class of alloys, which can be used for creating electromagnetic microactuators facilitating a linear motion. The concept of the hybrid MSM microactuator pursued is using a pair of discrete MSM strips sandwiched between microstators. For the microstator fabrication, MEMS technology is applied. The two MSM strips are elongated alternatively, with one strip showing strain when exposed to a magnetizing field, while the other one is mechanically collapsed by its elongating counterpart, and vice versa. For inducing the elongation in the MSM strips, a critical field strength H _crit has to be exceeded in vertical direction within the MSM strip. For analyzing what magnetic field strength is reached by the microstators and if it is greater than the critical field strength H _crit required to inducing a reorientation of the twin variants in the MSM material, magneto-optical measurements were carried out.