Effects of crystallographic orientation on the superelastic response of FeMnAlNi single crystals

Abstract The effects of crystal orientation on the tensile superelastic response of the Fe 43.5 Mn 34 Al 15 Ni 7.5 single crystalline shape memory alloy, oriented along the and directions were investigated. The single crystals aged at 200 °C for 3 h demonstrated superelastic strains of 3.6% along the orientation and 7.8% along the orientation. Although the theoretical transformation strain in the orientation is higher than that in the orientation, the oriented single crystals demonstrate better superelastic recovery in tension due to a higher number of active martensite variants, which promote better accommodation of internal strains and help minimize defect formation during transformation.