FeNiCoAlTaB superelastic and shape-memory wires with oligocrystalline grain structure

SCRIPTA MATERIALIA

卷:188

Article

Choi, Won Seok^1,2  Pang, Edward L.²  Choi, Pyuck-Pa¹  Schuh, Christopher A.² 

[1] Korea Adv Inst Sci & Technol, Dept Mat Sci & Engn, Daejeon 34141, South Korea

[2] MIT, Dept Mat Sci & Engn, Cambridge, MA 02139 USA

关键词: Superelasticity;    Shape-memory;    Wire-casting;    Oligocrystalline;    Ferrous alloy;   

DOI  :  10.1016/j.scriptamat.2020.06.067

来源: Elsevier

【 摘 要 】

FeNiCoAlTaB shape-memory alloys are desirable alternatives to other smart metallic materials owing to their low base metal and processing costs. These alloys, however, require strong texture via thermomechanical treatments or directional solidification to obtain good functional properties. Here, we demonstrate the fabrication of FeNiCoAlTaB shape-memory wires by a rapid, continuous wire-casting process. These untextured wires exhibit 7% superelastic strains and 1.2 GPa tensile strength after training, and show good cyclability and low stress hysteresis at room temperature. These properties far surpass previous reports in untextured polycrystalline ferrous alloys, an improvement which we attribute to their unique oligocrystalline grain structure. (C) 2020 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free