Effect of fatigue crack propagation in the shape memory alloy fiber reinforced smart composite

In this paper, the TiNi fiber reinforced/Polycarbonate(PC) composite material is developed, and its properties is studied. Conducting fatigue experiments, shape memory effect of the material for preventing fatigue crack growth are investigated. The fatigue behavior and crack propagation are observed under increasing temperature with a SEM servo-pulser, which is a fatigue testing instrument with scanning electron microscope. As the results, the effectiveness of fatigue resistance is confirmed. The shape memory effect and expansion behavior of the matrix caused by increasing temperature create the effect of the fatigue crack propagation control. It is verified that the controlling of fatigue crack growth is attributed to the compressive stress field in the matrix which is caused by shrinkage of the TiNi fibers above austenitic finishing temperature (At).