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Abstract. The giant magneto-strain effect is particularly attractive for actuator applications in micro-and nanometer dimensions as it enables contact-less control of large deformations, which can hardly be achieved by other actuation principles in small space. Two different approaches are being pursued to develop ferromagnetic shape memory (FSMA) microactuators based on the magnetically induced reorientation of martensite variants: (1) the fabrication of free-standing epitaxial Ni-Mn-Ga thin film actuators in a bottom-up manner by magnetron sputtering, substrate release and integration technologies and (2) the top-down approach of thickness reduction of bulk Ni-Mn-Ga single crystals to foil specimens of decreasing thicknesses (200 -40 µm) and subsequent integration. This review describes the fabrication technologies, procedures for thermo-mechanical training adapted to the quasi-two-dimensional geometries of film and foil specimens as well as the performance characteristics of state-of-the art actuators after processing and training.

3D printing technology through fused filament fabrication has found various industrial applications in the field of rapid manufacturing to fabricate prototypes and concept models. However, being the most popular technology, fused filament fabrication requires through understanding about the influence of the process parameters on resulting products. This investigation attempts to provide the terse behavior of the viscoelastic properties of fused filament fabrication processed with Poly Ethylene Terephthalate Glycol (PETG) samples considering the impact of fused filament fabrication process parameters. Dynamic mechanical analyzer is used to perform the dynamic mechanical analysis (DMA) and the dynamic response of fused filament fabrication PETG specimens is studied while they are subjected to dual cantilever loading under periodic stress. The fused filament fabrication process parameters such as, feed rate, layer thickness and infill density are considered. PETG parts are fabricated using 100% infill density at a feed rate of 50 mm/sec with three different layer thicknesses of 0.17 mm, 0.23 mm and 0.3 mm. DMA is performed with temperature ranging from room temperature to 130°C at five different frequency values of 1 Hz, 2 Hz, 5 Hz, 7 Hz & 10 Hz. The effect of process parameters of fused filament fabrication and frequencies on the viscoelastic properties of 3D printed PETG specimens is explored. The results reveled that, the storage module and loss module values are better for the specimens prepared with a layer thickness of 0.17 mm irrespective of the variation in the frequency values.

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