基于植物纤维细胞壁层级结构的仿生层合复合材料冲击及弯曲性能研究

Study on impact and flexural mechanical properties of biomimetic laminated composites based on the hierarchical structure of plant fiber cell walls

  • 摘要: 生物材料经过亿万年的进化,演化出多种有效的组成结构,赋予了生物材料优异的综合力学性能,为复合材料结构的强韧化设计提供了大量的灵感来源。本研究借鉴植物纤维细胞壁层级结构,开展仿生复合材料结构设计与力学性能研究。分别以细胞壁异质结构、细胞壁S2层微纤丝螺旋结构为模板,设计了两类仿生层合复合材料,并采用连续纤维3D打印技术实现仿生层合复合材料精确制备。结果表明:仿生异质复合材料结构冲击强度达65.5 kJ/m2,较传统结构提升35.7%;纤维螺旋角为30°时,仿生螺旋复合材料结构弯曲比吸能达1.32 J,较单向0°铺层复合材料提升50%;结合微观结构表征证实了仿生结构通过诱导裂纹偏转、延长扩展路径可实现复合材料强韧协同提升,为强韧性复合材料结构设计提供了有效途径。

     

    Abstract: Over billions of years of evolution, biological materials have developed diverse and efficient compositional structures, endowing them with outstanding comprehensive mechanical properties. These natural designs serve as a rich source of inspiration for enhancing the strength and toughness of composite materials. In this study, inspired by the hierarchical structure of plant fiber cell walls, we conducted research on the structural design and mechanical performance of biomimetic composites. Using the heterogeneous structure of the cell wall and the helical microfibril arrangement in the S2 layer as templates, two types of biomimetic laminated composites were designed and precisely fabricated via continuous fiber 3D printing. The results show that the impact strength of the biomimetic heterogeneous composite reached 65.5 kJ/m2, representing a 35.7% improvement over the conventional structure. When the fiber helix angle was 30°, the specific bending energy absorption of the biomimetic helical composite reached 1.32 J, which is 50% higher than that of the unidirectional 0° laminated composite. Microstructural characterization validates that crack deflection and extended propagation paths are the mechanisms behind the synergistic enhancement of strength and toughness in the biomimetic structures. This work provides a viable pathway for developing composite structures with combined high strength and toughness.

     

/

返回文章
返回