Stress wave mitigation at suture interfaces

This study investigated the stress wave dissipation in sinusoidal patterned suture interfaces that were inspired by sutures in biological materials. Finite element results showed that a sutured interface decreased the pressure 37% more than that at an unsutured interface, which arose from wave scattering and greater energy dissipation at sinusoidal boundaries. Stress wave scattering resulted in converting compressive waves (S11) into orthogonal flexural (S22) and shear waves (S12), which decreased both the peak pressure (attenuation) and wave speed (dispersion). Higher strain energy occurring at sutured interfaces brought energy loss within viscoelastic gap, too. In addition, we parameterized several variables related to the suture interfaces for their influence in stress wave mitigation. The following seven parameters were examined: (1) waviness of suture (ratio of suture height to suture period), (2) ratio of the suture height over the entire bar thickness, (3) gap thickness, (4) elastic modulus, (5) type of the boundary, (6) impactamplitude, and (7) impact duration. The final result of the parametric study revealed that the high ratio of the suture over the entire bar thickness had the greatest influence, followed by the short impact duration, and then by the low elastic modulus. Additionally, a high ratio of the suture over the entire bar thickness and low elastic modulus decreased the stress wave velocity as well. These findings can be applied for designing various synthetic damping systems so that man made engineering designs can implement the optimized sutures for impact scenarios.