Evolution of the cold-rolling and recrystallization textures in FeNiCoAlNbB shape memory alloy

摘要

The evolution of cold-rolling and recrystallization textures in the newly-developed ferrous shape memory alloy (FeNiCoAlNbB) was investigated and the improving mechanism on superelasticy of the severe cold-rolled alloy was discussed. A weaker copper rolling texture ({112}< 111 >) was formed in FeNiCoAlNbB alloy at relatively low rolling reductions (<= 80%); the copper rolling texture transformed to the Goss {110}< 001 > and brass {110}< 112 > orientations through twinning and dislocation slipping with the rolling reductions of 90%-95%; significantly enhanced rolling texture of a strong brass orientation was obtained with the rolling reduction of 98.5%. The 98.5% cold-rolled FeNiCoAlNbB alloy after solution treatment at 1220 degrees C for 1 h with strong {hk0}< 001 > recrystallization texture, followed by aging for 96 h at 600 degrees C exhibited good superelasticity of 3.2% with residual strain only 0.7%, and the tensile strength was approximately 960 MPa. Compared with the non-superelasticity in the as-forged FeNiCoAlNbB alloy, the considerably improving superelasticity in this alloy mainly attributes to the formation of strong favorable textures and the suppression of grain boundary precipitation. (C) 2016 Elsevier B.V. All rights reserved.