含损伤形状记忆合金增强智能结构的细观分析

从细观角度出发,运用变分原理对含损伤形状记忆合金(SMA)增强智能结构的热、力学行为进行了分析,导出了含损伤SMA增强智能结构的控制方程,给出了含损伤典型单元体的细观位移场、应力应变场的数学描述,建立了SMA增强智能结构的界面失效判据.在界面失效判据中,不仅包含了力载荷和温度载荷2种激励,其中温度激励隐含在有效自由回复应变当中,还包含了界面性能、SMA热力学性能、界面初始脱粘长度等因素.这些结果对认识含损伤SMA增强智能结构的强度自适应控制及其失效机理有一定意义,同时为进一步研究智能结构的完整性提供了相应的理论支持.

Meso-mechanical analyses of shape memory alloy wires reinforced smart structures with damages

The thermo-mechanical behaviors of shape memory alloy (SMA) wires reinforced smart structures with damages are analyzed through variational principle and meso-mechanical method.A governing equation on the structure is derived.Mathematical expressions on meso-displacement field,stress-strain field of typical element with damages are presented.A failure criterion for interface failure between SMA wires and matrix is established under two kinds of actuation which are dead-load and temperature,where the temperature is included in effective free restoring strain.In addition,there are some other composing factors in the failure criterion such as interface properties,thermodynamical properties of SMA,initial debonding length L-l,etc.The results are significant to understand structural strength self-adaptive control and failure mechanism of SMA wires reinforced smart structures with damages,and provide a theoretical foundation for further study on the integrity of SMA smart structures.