一种新的界面脱粘和纤维拔出模型

对纤维增强复合材料中界面的脱粘和纤维的拔出行为进行了研究,通过纤维间距d来考虑纤维之间的相互影响,改变脱粘段的剪切强度和粘结段的临界能量释放率,推导出了纤维拉拔荷载和纤维脱粘长度之间的变化关系,与StangH的模型进行了对比,当纤维间距较大时,纤维之间的相互影响相对较小,此时与StangH的单根纤维拉拔情况较为相符,但当纤维间距较小时,由于临近纤维的影响,使得在相同脱粘长度的情况下,纤维拉拔荷载和纤维拔出端位移有减小的趋势,改变复合材料板层的厚度,由于影响了基体的变形,界面的脱粘和纤维的拔出行为也受到了相应的影响。

New Model of Interfacial Debonding and Fiber Pullout

The problem of interfacial debonding and fiber pullout in fiber-reinforced brittle matrix composite material is analyzed. The interactions among the fibers mainly depend on the fiber space. Changing shear strength of debonding part or interfacial critical energy release rate of bond part the force/crack length relationship is predicted,the effect of one fiber to the others can be neglected while the fiber space gets large,which agrees with Stang H's conclusion. For a smaller fiber space,the load and the maximum fiber displacement decrease due to the effect of neighboring fibers when the crack length is fixed. If the board thickness of the specimen is changed,considering the matrix's distortion,the properties of interfacial debonding and fiber pullout are also changed.