High-temperature compatible, monolithic, 3D-printed magnetic actuators

We report the design, fabrication, and characterization of the first miniature 3D-printed, monolithic magnetic actuators that are compatible with high temperature (>200 °C) operation. The actuator is a cylindrical frame that holds a coil and a 24 mm diameter, 150 μm-thick membrane connected at its center to a piston with a cavity containing an embedded SmCo magnet. The fused filament fabrication (FFF) method is used to print the non-magnetic portion of the actuator out of pure nylon 12. The displacement of a single-layer membrane actuator is characterized for various coil bias voltages; a maximum displacement equal to 302 μm was obtained with 20V DC applied to the driving coil. Data analysis demonstrates that the magnetic force is proportional to the square of the current drawn by the coil -as expected from theory.