Numerical and experimental investigation of vibration and damping performance of additively manufactured mechanical metamaterials

• Twelve additively manufactured MM designs were investigated to check their vibration and damping performance. • Numerical analysis was carried out using ANSYS Workbench software, and experiments were performed using a hammer impact testing setup. • MM designs, having the same volume ratio, showed different natural frequencies in the range of 45–101 Hz, quite different behavior than the solid reference model, which had 161 Hz. • MM designs also showed different FRF peak amplitudes, highlighting varying vibration damping performance. • Octahedral lattice 2 design yields the highest percent damping ratio of 5.14%, showing superior vibration damping performance. Mechanical vibrations present significant challenges to advanced technologies—such as robotics, automobiles, aerospace, and additive manufacturing, where even minor disturbances can compromise structural integrity and performance. Mechanical metamaterials (MMs) offer innovative solutions for addressing these challenges, difficult to manage with conventional materials, and hence have emerged as a promising area of investigation. This research presents a comprehensive numerical and experimental investigation of the vibration and damping performance of twelve MM designs with varied morphologies compared with a solid reference design. The MM designs, modeled as cantilever beams in ANSYS SpaceClaim with a constant volume ratio of 32%, were fabricated using fused deposition modeling from acrylonitrile butadiene styrene material. Finite-element analysis and impact hammer experimental modal analysis were used to evaluate key vibration parameters, including impact force, coherence, time response, frequency response functions, mode shapes, natural frequencies, and damping ratios. The MM designs results show a lower natural frequency (45-101 Hz) than the solid reference (161 Hz), with numerical and experimental results in good agreement. Percent modal damping ratios for MM designs ranged from 1.96% to 5.14%, with most MM designs outperforming the solid design. Notably, the octahedral lattice 2 achieved the highest damping ( ζ ¯ e x p =5.14%), reducing the resonant peak response amplitude approximately by 81-84% for ζ b a s e =0.8-1%, demonstrating its strong potential for implementation in vibration sensitive applications.