Application of High Damping Cu Based SMA in Railway Collectors

In this work a composite material, made of thin strips of Cu based shape memory alloy (SMA) inserted in epoxy fiber glass, has been used for a new design of a lateral horn of railway collectors. The goal is the improvement of the structural damping in the correspondence of the first flexural mode of the horn, maintaining the same weight and flexural stiffness of the structure. For this purpose, CuZnAl SMA has been selected for its high damping properties and storage modulus among shape memory alloys. The specific contribution of the performance parameters associated with the SMA (specific damping, specific stiffness and volume fraction) and with the host material (flexural rigidity) were estimated. Moreover, samples of the component were realized with SMA alloy and a commercial non shape memory brass, to take into account possible contribution to damping of the interface between metal thin strip and the epoxy fiber glass.