A novel training-free cast Fe–18Mn–5.5Si–9.5Cr–4Ni shape memory alloy with lathy delta ferrite

The microstructures and shape recovery of a cast Fe–18Mn–5.5Si–9.5Cr–4Ni alloy were investigated. We attained lathy ferrite in this cast alloy and a 94% recovery of 3.6% deformation only through annealing this alloy at 973 K. The subdivision of grains by lathy ferrite and its resulting formation of stress-induced martensite bands in a domain-specific manner accounted for the high shape recovery. This work provides a novel idea of developing training-free Fe–Mn–Si shape memory alloy with a high shape recovery.