Abstract: In this paper, a new method that is utilizing the unique mechanical properties and physical function of Shape Memory Alloy (SMA) which is embedded in the component to detect crack and actively control the crack growth is presented. The Shape Memory Alloys, and NiTi wire in particular, have many unique characteristics and behavior. For example, they have larger electric resistivity and higher sensitivity to strains, and will produce a large recovery force when heated, etc. The SMA-NiTi wires are embedded in the epoxy plate and tensile specimens are made. Both photoelastic experiment and numerical analysis are investigated. The experiment and calculation results show that this method can be used to the crack-detecting and actively control the crack growth, and the effect is obvious.

Key words: crack-detectipg, active control the crack growth, shape memory alloy, stress intensi-ty factor, recovery force