A eutectic dual-phase design towards superior mechanical properties of heusler-type ferromagnetic shape memory alloys

Journal Article · Mon Sep 30 00:00:00 EDT 2019 · Acta Materialia

DOI:https://doi.org/10.1016/j.actamat.2019.09.054· OSTI ID:1630311

Wu, Zhigang  ^[1]; Liang, Zhiwen ^[2]; Zhang, Yajiu ^[2]; Liu, Zhuhong ^[3]; Zhang, Junsong ^[4]; Motazedian, Fakhrodin ^[4]; Bakhtiari, Sam  ^[4]; Shariat, Bashir Samsam  ^[4]; Liu, Yinong  ^[4]; Ren, Yang ^[5]; Yang, Hong  ^[4]

---

1. Guangzhou Univ. (China); Univ. of Western Australia, Perth, WA (Australia)
2. Guangzhou Univ. (China)
3. Univ. of Science and Technology Beijing (China)
4. Univ. of Western Australia, Perth, WA (Australia)
5. Argonne National Lab. (ANL), Argonne, IL (United States)

Heusler-type ferromagnetic shape memory alloys possess attractive multifunctional properties, including magnetic field induced shape memory effect, magnetoresistance and magnetocaloric effect, owing to the unique concurrent magnetic and martensitic transformations. However, these intermetallics generally exhibit intrinsic high brittleness and low strength, which severely impede their workability for processing and applicability in real use. In this study, we demonstrate a new grain refining strategy by means of eutectic solidification to improve the mechanical properties in Ni-Mn-Sn-Fe alloys. In a fully eutectic microstructure, the average γ lamellae thickness was refined to ~170 nm and the composite showed a compressive strength of 1950 MPa, ductility of 19.5%, Young’s Modulus of 38 GPa, pseudoelasticity of 3.2% and high mechanical cyclic stability. The high mechanical performance is attributed to the effect of departmentalization of the brittle Heusler alloy by the densely distributed γ phase fine lamellae in resisting crack propagation. The eutectic Heusler composite exhibited a metamagnetic phase transformation, with a magnetic entropy change of 10.2 J/kg·K and a refrigeration capacity of 168 J/kg in a field change of 5 T.

• Research Organization: Argonne National Lab. (ANL), Argonne, IL (United States)
• Sponsoring Organization: National Natural Science Foundation of China (NSFC); Natural Science Foundation of Guangdong Province; Australian Research Council; USDOE Office of Science (SC)
• Grant/Contract Number: AC02-06CH11357
• OSTI ID: 1630311
• Alternate ID(s): OSTI ID: 1694073
• Journal Information: Acta Materialia, Vol. 181, Issue C; ISSN 1359-6454
• Publisher: Elsevier
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
Ductility
Grain refining
Magnetic entropy change
Eutectic microstructure
Heusler alloys