Variability in elastic vibration response of additively manufactured materials: A round robin study.

The rapid growth of research in advanced acoustic materials has been enabled by contemporary growth in additive manufacturing advancement and accessibility. This report provides a quantitative evaluation of variability in the elastic vibration response of structures fabricated using fused deposition modeling. The approach in this study involves assembling a sample set from six institutions via an interlaboratory round robin study. Slender beam samples were fabricated using fused deposition modeling and a standardized commercial filament and printed on whichever commercial printers were available at each institution. To quantify variability in fabrication of both bulk material and metamaterial-inspired features, two sample sets were requested and tested, a set of plain beams and a set of beams with embedded resonator. All samples were measured for dimensional accuracy and dynamic performance using a vibration shaker using a laser Doppler vibrometer. Measured resonance response of each set of samples revealed that the variability between printers was roughly 20% in bulk dynamic properties and as large as 280% in coupled resonator-beam dynamic performance. The study provides design bounds for metamaterial design across various printer hardware and highlights the importance of understanding repeatability using this fabrication approach.