Magnetically tunable damping in composites for 4D printing

Composite materials are being used in the design of new devices to produce more functional, cheap and ondemand products. In particular, 3D printing technology based on composites opens a huge field enabling the freedom of design and the ability to manufacture complex structures. In this context, the analysis of the functional properties of printable composites is of great importance. The work is focused on the analysis of the mechanical damping of a composite made with different concentrations of a Ni45Mn36.7In13.3Co5 metamagnetic shape memory alloy into an UV-curing polymer. The composites provide a bulk material containing very brittle metallic mu-particles that can be handled for technological applications. Damping and dynamic modulus of the composites were modified with small magnetic fields below 100 kA/m, proving that the damping capacity can be tuned by applying an external magnetic field. From the measurements, it has been also possible to determine the intrinsic damping and moduli of the alloy particles, which show the characteristic properties linked to the MT. These preliminary results allow proposing this composite material as a potential functional material to be used in the design of printable devices for magneto-mechanical damping applications.