Overcoming Dynamic Stiffness-Damping Trade-Off with Structural Gradients in 3D Printed Elastomeric Gyroid Lattices

Abstract

Background

Creating structural materials with mesoscale architectures and functional gradients facilitates the synergistic achievement of outstanding strength, stiffness, and damping, which is essential for effectively mitigating extreme mechanical waves and vibrations. In contrast to conventional stochastic foams, deterministic architected materials fabricated by three-dimensional (3D) printing, such as minimal surface-based gyroid lattices, offer a broad design space to achieve exceptional mechanical performance with efficient material utilization.

Objective

Using 3D printed elastomeric gyroid lattices as a model cellular material system, this work focuses on studying the quasi-static and dynamic mechanical behavior of soft gyroid lattices made from viscoelastic elastomeric materials, as well as the effects of incorporating pre-compressive strain as a strategy to tailor the dynamic performance of gradient gyroid lattices.

Methods

Soft gyroid structures based on viscoelastic elastomeric polymer were 3D printed by stereolithography (SLA). We performed quasi-static compression up to 70% strain to study the mechanical behavior and energy absorption performance of the 3D printed gyroid lattices. Dynamic mechanical analyses in compression mode at different applied static precompressions were conducted to understand the effects of structural gradients on dynamic material properties.

Results

We show that the integration of viscoelastic elastomeric material with gradient architecting—compared with uniform periodic lattices—leads to superior independent control over dynamic material properties. Under harmonic excitations, by leveraging the structural gradient of the gyroid lattice with applied static precompression, we demonstrate a greater tunability of dynamic stiffness in graded-gyroids compared with the uniform gyroid structure. In graded-gyroids, we achieve a substantial enhancement in dynamic stiffness (over 600%) while maintaining the inherent damping capabilities, thus overcoming the common trade-off between stiffness and damping seen in engineering materials.

Conclusion

Our study shows the potential of 3D printed architected cellular structures with tailored structural gradients as advanced lightweight structural materials for extreme damping, shock-absorbing, and robust robotic material applications.