Novel femur-like multimodal ultrahigh strength structure with superb freedom based on the improvement strategy of curvature fabricated by additive manufacturing

Abstract

Based on the microstructure of biological femur, the femur-like multimodal surface structures are designed. But they exhibit fracture behavior when the porosity changes, resulting in structural failure. The high curvature surface factor is introduced to improve the fracture behavior of the biomimetic surface structure. Combine the high curvature surface factor to construct novel biomimetic homogenized surface structures. Novel radial gradient surface structures and axial gradient surface structures are designed based on the construction concept of cone functions and linear functions gradients. Theoretical, experimental and numerical methods are used to investigate the mechanical properties of novel biomimetic multimodal surface structures. Euler theory states that the properties of lattice structures are determined by the relative density of structures. The load distribution in the radially gradient structure is uniform, and the deformation mode presents overall failure, which can achieve better resistance and dissipation of the load. The deformation modes of axial gradient structures present layered failure. The underlying mechanism of the difference in mechanical properties of biomimetic multimodal structures is explained in detail. It’s very important significance for targeted application in protective engineering.

Keywords

• Fracture defect
• Curvature improvement
• Femur-like multimodal surface structure
• Superb freedom
• Euler theory