Nanoindentation/atomic force microscopy analyses of ε-martensitic transformation and shape memory effect in Fe–28Mn–6Si–5Cr alloy

Nanoindentation was conducted to investigate the stress-induced ε-martensitic transformation behavior and the shape memory effect in a Fe–28Mn–6Si–5Cr alloy. The shape memory effect was evaluated from the volume change in an indent mark caused by annealing measured by atomic force microscopy. Using the load–displacement (P–h) data obtained from nanoindentation, the plot of P/h vs. h showed two types of slopes, corresponding to the ε-martensitic transformation and slip deformation, and exhibited a correlation with the shape recovery ratio.