超细纤维增强复合材料Ⅰ型层间断裂韧性分析

Improvement of mode Ⅰ interlaminar fracture toughness of composites reinforced by ultrathin fibers

采用静电纺丝技术制备了厚度约0.1 mm的超细纤维无纺布薄膜,并入层合板中间界面,固化成型后加工为双悬臂梁(DCB)试样。根据ASTM D5528标准测试了Ⅰ型层间断裂韧性。实验结果表明,增强试样比空白试样的Ⅰ型临界应变能释放率(GⅠC)提高了约35%。同时采用有限元分析方法研究了含无纺布薄膜试样和空白试样的裂纹扩展过程,数值结果与实验结果吻合较好,更好地解释了含无纺布薄膜层合板的层间断裂机理。

The non-woven ultrathin fibers film with a thickness about 0. 1 mm was made by use of electrospinning. This film was incorporated into the middle interface of a composite laminate, which was cured and cut into double cantilever beam （DCB） specimens. Blank DCB specimens were prepared in the same way. The mode Ⅰ interlaminar fracture toughness was measured according to ASTM D5528 standard. The experimental results show that the mode Ⅰ critical strain energy release rate is improved about 35% by using the non-woven film compared to the blank specimens. The propagation of cracks for those two kinds of specimens is analyzed by use of the FE method. It shows that the numerical results are well in agreement with the experimental results and a better understanding of the fracture mechanics is obtained by the numerical analysis.