Thermoelastic martensitic transformation and superelasticity in Fe-Ni-Co-Al-Nb-B polycrystalline alloy

The effects of the addition of Nb and B on grain boundary precipitation, martensitic transformation and superelasticity were investigated in the Fe-Ni-Co-Al alloys. The addition of Nb increases the hardness and the martensitic transformation changes from non-thermoelastic to thermoelastic, while the addition of B is effective for suppressing the formation of brittle grain boundary precipitates. By the recrystallization texture developed by 98.5% cold-rolling and annealing, high ductility and superelasticity with 5% recoverable strain were realized in the Fe-28Ni-17Co-10.5Al-2.5Nb-0.05B polycrystalline alloy. (C) 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.