Mechanical Behavior of Deer Antler Under Quasi-static and Dynamic Loading: Experiments and Modeling

Abstract

Both quasi-static and dynamic tests were performed on cortical tissue from naturally shed deer antler. For both loading conditions, indirect Brazilian disc specimens were subjected to loading transverse to the osteon direction. Dynamic Brazilian tests were conducted using a compression Split-Hopkinson Pressure Bar (SHPB), while conventional tensile tests were performed along the primary axis of the osteons. Tensile tests along the osteon axis yielded strengths up to approximately three times higher than those in the transverse direction. The ultimate stress in the dynamic tests was around 90 MPa and exhibited rate sensitivity. Scanning Electron Microscopy (SEM) images revealed that lamellae (both concentric and interstitial) oriented perpendicular to the loading direction did not significantly contribute to the mechanical strength in the indirect tests. This observation was corroborated by the small surface area fraction of the interstitial lamellae within a complete osteon unit. Finally, a constitutive equation was developed to model the elastic and inelastic response of the material under quasi-static tension. This model incorporates the contribution of the interfibrillar matrix to the material’s strength, using realistic parameters consistent with experimental data.