Effects of grain refinement on the structure and properties of a CuAlMn shape memory alloy

To further enhance the performances of Cu-based shape memory alloys (SMAs), grains of a CuAlMn SMA were efficiently refined by using Cu51Zr14 as the inoculant. The effects of grain size on the microstructure, tensile mechanical properties as well as low frequency damping behaviors of the CuAlMn SMA were studied. It was found that the mean grain size of the CuAlMn SMA could be reduced from around 1050 µm to around 37 µm. And it was very interesting that both the tensile mechanical property and the damping capacity at relatively low temperatures increased with the decrease of the mean grain size of the CuAlMn SMA. The associated mechanisms were discussed.