Shape memory alloys (SMAs) possess both sensing and actuating functions due to their shape memory effect, pseudo-elasticity, high damping capability and other remarkable properties. Combining the SMAs with other materials can create intelligent or smart composites by utilizing the unique properties of SMAs. In this paper, epoxy resin composites filled with NiTi alloy short fibers and particles were fabricated and their mechanical properties investigated. Owing to the addition of SMA fillers, the flexural rigidity of SMA/epoxy composites increases. Especially, the storage modulus increases remarkably with increasing filler content in the high temperature region. The experimental results show that the addition of just 3.5% of SMA fillers to epoxy resin resulted in a remarkable increment of storage modulus, which is six times as large as that of epoxy bulk (ER3). The storage modulus reaches the maximum at the SMA phase transformation temperature of approximate 120 o C. The loss factor of SMA/ER3 composites increases with the increment of SMA filler contents. Based on the Halpin-Tsai theory, moreover, a model for the laminated plates with SMA fillers is presented to predict the dynamic mechanical properties. Compared to the experimental results, reasonable prediction of the dynamic behavior is obtained based on the present models.

Shape memory alloys (SMAs) possess both sensing and actuating functions due to their shape memory effect, pseudo-elasticity, high damping capability and other remarkable characteristics. Combining the unique properties of SMAs with other materials can create intelligent or smart composites. In this paper, epoxy resin composites filled with NiTi alloy short fibers were developed. Microstructure was observed using digital HF microscope. The dynamic mechanical properties were investigated by measuring the first vibration mode of clamped cantilever beams and by dynamic mechanical analysis (DMA). Moreover, the natural frequency of SMA composites was predicted theoretically. As a result, the temperature dependency of vibration property and DMA characteristics is affected largely due to an addition of SMA short fibers. The vibrational characteristics of SMA composites can be improved by the addition of small amounts of SMA short fibers. The addition of 3.5wt% of SMA short fiber content to epoxy resin resulted in the maximum increment in both natural frequency and storage modulus. This suggested there exists an optimum SMA fiber content for vibration characteristics.

Shape memory alloy (SMA) is commercially available for a variety of actuator and damping materials. Recently, SMA wires have also become commercially available for the design of smart composite structures because SMA wires with a small diameter can be easily .

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