Fabrication and internal friction behaviors of novel porous CuAlMn shape memory alloy filled with polystyrene

Polystyrene layer with adjustable thickness was introduced into a porous CuAlMn shape memory alloy, and the internal friction behaviors of the resultant materials were investigated using a multifunctional internal friction apparatus through the method of forced vibration. Two relaxational internal friction peaks accompanied by a sharp decrease of the relative dynamic modulus were found at around 95 °C and 119 °C, respectively. The two internal friction peaks have been ascribed to the relaxation process in a thermal equilibrium state of the polystyrene over its glass transition temperature. The damping capacity of the resultant materials was greatly elevated due to the superposition of several individual damping sources in them.

► Novel polystyrene/CuAlMn composites were fabricated by an innovative method.
► The composites show greatly superior damping capacity to the porous CuAlMn SMAs.
► Two relaxational internal friction peaks were found during the glass transition of the polystyrene.
► Mechanisms of the internal friction peaks and damping enhancement were discussed.