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Updated: Jul 26, 2025
11:11
Experimental Methods for Investigation of Shape Memory Based Elastocaloric Cooling Processes and Model Validation
Published on: May 2, 2016
11.1K
Pd2 MnGa Metamagnetic Shape Memory Alloy with Small Energy Loss.
Tatsuya Ito1, Xiao Xu1,2, Atsushi Miyake3
1Department of Materials Science, Graduate School of Engineering, Tohoku University, Aoba-yama 6-6-02, Sendai, 980-8579, Japan.
Advanced Science (Weinheim, Baden-Wurttemberg, Germany)
|June 13, 2023
Summary
A new Palladium-Manganese-Gallium (Pd2MnGa) metamagnetic shape memory alloy (MMSMA) exhibits minimal energy loss and hysteresis during its transformation. This breakthrough offers potential for highly efficient MMSMAs in actuator applications.
Area of Science:
- Materials Science
- Metallurgy
- Solid State Physics
Background:
- Metamagnetic shape memory alloys (MMSMAs) offer unique properties like magnetostrain and magnetocaloric effects.
- High energy loss (Edis) and hysteresis during martensitic transformation limit MMSMA applications.
Purpose of the Study:
- To develop a novel Pd2MnGa Heusler-type MMSMA with significantly reduced energy loss and hysteresis.
- To investigate the material properties and performance of this new MMSMA.
Main Methods:
- Microstructural and crystallographic analysis.
- Magnetic property and martensitic transformation characterization.
- Measurement of magnetic-field-induced strain and energy dissipation.
Main Results:
- A martensitic transformation from L21 to 10M structures occurred at 127.4 K with 1.3 K thermal hysteresis.
- A reverse martensitic transformation was induced by a magnetic field at 120 K with very low Edis (0.3 J/mol) and magnetic hysteresis (7 kOe).
- A significant magnetic-field-induced strain of 0.26% was achieved.
Conclusions:
- The Pd2MnGa alloy demonstrates exceptionally low energy loss and hysteresis, attributed to good lattice compatibility.
- This material shows promise for developing high-efficiency MMSMAs and advanced actuator technologies.
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