This thesis presents the use of 3D printed metamaterials for low-frequency vibration isolation in structural dynamics. The basic representative cell of the metamaterial consists of a resonator and a structure with nonlinear stiffness, exhibiting high static and low dynamic stiffness. The so-called quasi-zero stiffness enables the appearance of band gaps at very low frequencies. Through the considered basic representative cell, whose periodic arrangement forms the metamaterial, the properties of an infinitely long metamaterial are determined by analytically deriving dispersion curves. The thermoactive properties of the used conductive filament allow for adaptive stiffness control and adaptation of the band gap through Joule heating. Numerical simulations of the transmission of a finite chain of cells confirm the existence of band gaps at the same frequencies as the dispersion curves. The final metamaterial and experimental transmission show the existence of band gaps capable of reducing transmission by 30 to 40 dB, but these are located at higher frequencies than predicted by theory due to material creep.
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