Most biological composites including bones, teeth and nacres have superior fracture resistance properties than that of their constituents. Their complex mixing of stiff and soft constituents enables energy dissipation ahead of the crack tip and contributes to enhance the fracture performance. In this study, phase-field based modeling is used to understand the fracture resistance of bio-inspired designs. Phase-field based topology optimization is then proposed to further improve the fracture resistance of these composite structures. The fracture process from damage to multiple crack propagation and ultimately to failure is fully studied. Numerical experiments show that significant enhancement of the fracture toughness, failure strain and overall strength can be achieved over the homogeneous constitutive stiff material.

包括骨骼，牙齿和珍珠质在内的大多数生物复合材料均具有比其成分更好的抗断裂性能。它们对硬质和软质成分的复杂混合使能量能够在裂纹尖端之前散发，并有助于增强断裂性能。在这项研究中，基于相场的建模用于理解生物启发设计的抗断裂性。然后提出基于相场的拓扑优化，以进一步提高这些复合结构的抗断裂性。全面研究了从破坏到多次裂纹扩展，再到破坏的断裂过程。数值实验表明，与均质本构刚度材料相比，断裂韧性，破坏应变和整体强度均得到了显着提高。