形状记忆合金纤维在变轴力作用下的力学性能研究

对形状记忆合金纤维拔出的力学模型进行了探讨和简化。以一维的Liang-Rogers本构模型和Tanaka给出的指数型马氏体含量关系为基础,给定界面摩擦力的取值范围,并考虑其对纤维的作用,给出了恒温条件下加载和卸载过程中脱胶区纤维的伸长量与外载荷、摩擦力的关系式,及相关的系列曲线图,得到了界面摩擦力对形状记忆合金纤维力学特性的一些影响。由于余弦和指数模型得到的结果吻合良好,该文的变轴力模型具有一定的合理性。

MECHANICAL PROPERTIES OF SMA FIBER UNDER VARYING AXIAL FORCE

The mechanical model of SMA fiber pull-out is discussed and simplified in the paper. On the basis of one-dimensional Liang-Rogers constitutive model and Tanaka exponent model for Martensite volume fraction, with limited numerical value of interfacial friction effect considered, the functional relationships between the displacement of fiber in the pull-out zone and the external load and friction upon loading and unloading are deduced under isothermal condition. In addition, a series of relative curves are given, and the influences of interfacial friction to the mechanical properties of SMA fiber are obtained. The good agreement of the results from cosine and exponent models indicates that the varying axial force model is reasonable to some extent.