3-D printed membrane-type acoustic metamaterials with tailored performance

While traditional membrane-type acoustic metamaterials act as effective lightweight sound insulation materials, their geometries can neither be easily customized nor incorporated into other acoustic designs in a single workflow. Here, we leverage our established techniques at 3-D printing thin membranes to create custom acoustic metamaterials with tailored performance that can be easily implemented into other acoustic designs without any post-processing. In this study, we present the workflow to additively manufacture flexible membranes with added textural features using low-cost extrusion-based printing methods. Using a custom G-code, we print membranes with controlled mass, stiffness, and porosity while superimposing various surface pattern designs. Using a four-microphone normal-incidence impedance tube setup, we demonstrate the effect of each parameter on the membrane’s sound transmission loss behavior and compare the results against traditional acoustic mass law.