Laser surface remelting of a Cu-Al-Ni-Mn shape memory alloy

Cu-based shape memory alloys (SMA) show better thermal and electrical conductivity, lower cost and are easier to process than more traditional Ti-based SMA. However, they show low ductility, which can be improved by grain refinement and reduction of microstructural segregations. This can be obtained by a laser remelting treatment. The aim of this work was to produce and characterize Cu-11.8Al-3.2Ni-3Mn SMA plates, which was laser surface remelted with a power of 300 W and scanning speeds of 100, 300 and 500 mm/s. The plates were characterized by optical microscope, X-ray diffraction and tensile tests. The remelted region shows a refined microstructure, which improved the mechanical properties of the plates making this treatment a promising method for improving the mechanical properties of Cu-based SMA. (author)