曲面小构件变形状态的全场检测问题研究

Research on Full-field Measurement of Deformation of Small Curved Components

针对传统方法难以测量曲面小构件非均匀变形的问题,比如受力时发生变形失稳的镍钛形状记忆合金微管,提出了显微成像法和三维形貌扫描法。它们以非接触和全场的方式追踪构件在不同变形状态下表面标记点的位置,从而获取位移数据,并通过固体力学中经典的几何方程计算得到应变结果。实验证明了所提出方法的易操作性和可靠性,还得到了对于相变材料的力学问题的研究具有重要意义的结果。

Traditional methods are hardly applicable to the measurement of non-uniform deformation of small curved components, such as NiTi shape memory alloy microtubes which may exhibit deformation instability under mechanical force. Thus microscopy and 3-D profilometry are put forward as the solution. These methods are full-field and non-contact to track the positions of point marks on the surface of the specimen in different deformation states. Accordingly, displacement field can be built and strain can be calculated by the geometry equations of solid mechanics. The methods have been proven by experiment to be effective and reliable. They have helped to get significant results for the research on mechanics of phase-transformation materials.