通常NiTi纤维圆柱体剪滞模型是通过界面传递应力,界面剪应力较大时,界面将产生脱粘。将两端有小垫片的NiTi纤维埋入基体中,构成一种新的NITi纤维圆柱体剪滞模型,在一定的简化条件下,针对马氏体逆相变过程,对纤维轴应力、界面剪应力的分布及应力传递进行分析。分析结果表明,与通常模型比较,新模型可通过界面和小垫片传递应力,减小界面剪应力峰值,能充分发挥NiTi纤维的作动效应。此外还讨论了小垫片几何尺寸对应力分布及传递的影响。
The stress transfer between the fiber and the matrix only depends on the interface in conventional cyl- inder model with a prestrained NiTi fiber,when the maximum interface shear stress is relatively high,interfacial debond would take place. In this paper,a prestrained NiTi fiber with a pad at it's ends is embedded to the matrix to construct a new cylinder model. During the reverse transformation, and under the simplicity conditions, the stress distributions of the NiTi fiber and the interface,and the stress transfer are analysed. Compared to the conventional model, it is shown that the stress transfer between the fiber and the matrix depends on not only the interface but also the pad in the new model, and the maximum interface shear stress is relatively low. The effect of the NiTi fiber actuation can be brought into full play. Additionally,the size effect of the pad on the stress distribution and the stress transfer is discussed.