Orientation dependence of superelasticity in FeMnAlNi single crystals under compression

Abstract

The orientation dependence of the martensitic transformation characteristics and superelasticity were investigated in the Fe43.5Mn34Al15Ni7.5 single crystalline shape memory alloy along the [100], [111] and [123] orientations under compression. Solution heat treated samples exhibited a strong orientation dependence of the slopes for the stress vs. temperature phase diagrams (i.e. Clausius-Clapeyron slopes), while peak-aged samples demonstrated reduced orientation dependence. Maximum superelastic strains determined in the experiments along various single crystal orientations match well with the theoretical predictions.