Multifunctional TEG-PCM-Actuator for a Thermoelectric Metamaterial

In our work, we present an easy-to-fabricate multifunctional actuator design featuring a thermoelectric generator (TEG) doubling as a Peltier element, enabling heating and cooling of its faces when a current is supplied. The linear actuator is comprised of a 3D-printed cavity filled with phase change material (PCM) that actuates a brass piston outside a cover membrane made from silicone (PDMS). The final setup, which is formed by connecting two of these linear actuators to opposite sides of a TEG, establishes an electro-mechanical system in which the TEG can function both as a Peltier element to perform controlled paraffin expansion/contraction on demand, and as an energy harvesting device to capture the electrical energy generated during phase transitions of the two dissimilar paraffin-waxes. This setup can be used for biaxial actuation by incorporating an acrylic auxetic metamaterial model driven by the force of individual pistons along one of the two axes. The work shows a proof of concept for further investigation and development in the area of thermoelectric metamaterials.